Extract more of the mouse logic from EventHandler

third_party/WebKit/Source/core/input/EventHandler.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2012 Digia Plc. and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 12 matching lines @@
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/input/EventHandler.h"
 
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
 #include "core/HTMLNames.h"
 #include "core/InputTypeNames.h"
-#include "core/clipboard/DataObject.h"
 #include "core/clipboard/DataTransfer.h"
 #include "core/dom/DOMNodeIds.h"
 #include "core/dom/Document.h"
 #include "core/dom/TouchList.h"
 #include "core/dom/shadow/FlatTreeTraversal.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/EditingUtilities.h"
 #include "core/editing/Editor.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/SelectionController.h"
-#include "core/events/DragEvent.h"
 #include "core/events/EventPath.h"
 #include "core/events/GestureEvent.h"
 #include "core/events/KeyboardEvent.h"
 #include "core/events/MouseEvent.h"
 #include "core/events/PointerEvent.h"
 #include "core/events/TextEvent.h"
 #include "core/events/TouchEvent.h"
 #include "core/events/WheelEvent.h"
 #include "core/fetch/ImageResource.h"
 #include "core/frame/Deprecation.h"
@@ skipping 15 matching lines @@
 #include "core/layout/HitTestResult.h"
 #include "core/layout/LayoutPart.h"
 #include "core/layout/LayoutTextControlSingleLine.h"
 #include "core/layout/LayoutView.h"
 #include "core/layout/api/LayoutViewItem.h"
 #include "core/loader/DocumentLoader.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/page/AutoscrollController.h"
 #include "core/page/ChromeClient.h"
-#include "core/page/DragController.h"
 #include "core/page/DragState.h"
 #include "core/page/FocusController.h"
 #include "core/page/FrameTree.h"
 #include "core/page/Page.h"
 #include "core/page/TouchAdjustment.h"
 #include "core/page/scrolling/ScrollState.h"
-#include "core/paint/PaintLayer.h"
 #include "core/style/ComputedStyle.h"
 #include "core/style/CursorData.h"
 #include "core/svg/SVGDocumentExtensions.h"
 #include "platform/PlatformGestureEvent.h"
 #include "platform/PlatformTouchEvent.h"
 #include "platform/PlatformWheelEvent.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/TraceEvent.h"
 #include "platform/WindowsKeyboardCodes.h"
 #include "platform/geometry/FloatPoint.h"
@@ skipping 21 matching lines @@
     Node* targetNode = mev.innerNode();
     if (!targetNode || !targetNode->parentNode())
         return true;
     return targetNode->isShadowRoot() && isHTMLInputElement(toShadowRoot(targetNode)->host());
 }
 
 } // namespace
 
 using namespace HTMLNames;
 
-// The link drag hysteresis is much larger than the others because there
-// needs to be enough space to cancel the link press without starting a link drag,
-// and because dragging links is rare.
-static const int LinkDragHysteresis = 40;
-static const int ImageDragHysteresis = 5;
-static const int TextDragHysteresis = 3;
-static const int GeneralDragHysteresis = 3;
-
-// The amount of time to wait before sending a fake mouse event triggered
-// during a scroll.
-static const double fakeMouseMoveInterval = 0.1;
-
 // The amount of time to wait for a cursor update on style and layout changes
 // Set to 50Hz, no need to be faster than common screen refresh rate
 static const double cursorUpdateInterval = 0.02;
 
 static const int maximumCursorSize = 128;
 
 // It's pretty unlikely that a scale of less than one would ever be used. But all we really
 // need to ensure here is that the scale isn't so small that integer overflow can occur when
 // dividing cursor sizes (limited above) by the scale.
 static const double minimumCursorScale = 0.001;
 
 // The minimum amount of time an element stays active after a ShowPress
 // This is roughly 9 frames, which should be long enough to be noticeable.
 static const double minimumActiveInterval = 0.15;
 
-#if OS(MACOSX)
-static const double TextDragDelay = 0.15;
-#else
-static const double TextDragDelay = 0.0;
-#endif
-
 enum NoCursorChangeType { NoCursorChange };
 
-enum class DragInitiator { Mouse, Touch };
-
 class OptionalCursor {
 public:
     OptionalCursor(NoCursorChangeType) : m_isCursorChange(false) { }
     OptionalCursor(const Cursor& cursor) : m_isCursorChange(true), m_cursor(cursor) { }
 
     bool isCursorChange() const { return m_isCursorChange; }
     const Cursor& cursor() const { ASSERT(m_isCursorChange); return m_cursor; }
 
 private:
     bool m_isCursorChange;
     Cursor m_cursor;
 };
 
 EventHandler::EventHandler(LocalFrame* frame)
     : m_frame(frame)
-    , m_mousePressed(false)
-    , m_capturesDragging(false)
-    , m_mouseDownMayStartDrag(false)
     , m_selectionController(SelectionController::create(*frame))
     , m_hoverTimer(this, &EventHandler::hoverTimerFired)
     , m_cursorUpdateTimer(this, &EventHandler::cursorUpdateTimerFired)
-    , m_mouseDownMayStartAutoscroll(false)
-    , m_fakeMouseMoveEventTimer(this, &EventHandler::fakeMouseMoveEventTimerFired)
-    , m_svgPan(false)
     , m_eventHandlerWillResetCapturingMouseEventsNode(0)
-    , m_clickCount(0)
     , m_shouldOnlyFireDragOverEvent(false)
-    , m_mousePositionIsUnknown(true)
-    , m_mouseDownTimestamp(0)
     , m_scrollManager(new ScrollManager(frame))
-    , m_mouseEventManager(new MouseEventManager(frame))
+    , m_mouseEventManager(new MouseEventManager(frame, m_scrollManager))
     , m_keyboardEventManager(new KeyboardEventManager(frame, m_scrollManager))
     , m_pointerEventManager(new PointerEventManager(frame, m_mouseEventManager))
-    , m_gestureManager(new GestureManager(frame, m_scrollManager, m_pointerEventManager, m_selectionController))
+    , m_gestureManager(new GestureManager(frame, m_scrollManager, m_mouseEventManager, m_pointerEventManager, m_selectionController))
     , m_activeIntervalTimer(this, &EventHandler::activeIntervalTimerFired)
 {
 }
 
-EventHandler::~EventHandler()
-{
-    ASSERT(!m_fakeMouseMoveEventTimer.isActive());
-}
-
 DEFINE_TRACE(EventHandler)
 {
     visitor->trace(m_frame);
-    visitor->trace(m_mousePressNode);
     visitor->trace(m_selectionController);
     visitor->trace(m_capturingMouseEventsNode);
-    visitor->trace(m_nodeUnderMouse);
     visitor->trace(m_lastMouseMoveEventSubframe);
     visitor->trace(m_lastScrollbarUnderMouse);
-    visitor->trace(m_clickNode);
     visitor->trace(m_dragTarget);
     visitor->trace(m_frameSetBeingResized);
     visitor->trace(m_scrollManager);
     visitor->trace(m_mouseEventManager);
     visitor->trace(m_keyboardEventManager);
     visitor->trace(m_pointerEventManager);
     visitor->trace(m_gestureManager);
     visitor->trace(m_lastDeferredTapElement);
 }
 
-DragState& EventHandler::dragState()
-{
-    DEFINE_STATIC_LOCAL(DragState, state, (new DragState));
-    return state;
-}
-
 void EventHandler::clear()
 {
     m_hoverTimer.stop();
     m_cursorUpdateTimer.stop();
-    m_fakeMouseMoveEventTimer.stop();
     m_activeIntervalTimer.stop();
-    m_nodeUnderMouse = nullptr;
     m_lastMouseMoveEventSubframe = nullptr;
     m_lastScrollbarUnderMouse = nullptr;
-    m_clickCount = 0;
-    m_clickNode = nullptr;
     m_frameSetBeingResized = nullptr;
     m_dragTarget = nullptr;
     m_shouldOnlyFireDragOverEvent = false;
-    m_mousePositionIsUnknown = true;
-    m_lastKnownMousePosition = IntPoint();
-    m_lastKnownMouseGlobalPosition = IntPoint();
     m_lastMouseDownUserGestureToken.clear();
-    m_mousePressNode = nullptr;
-    m_mousePressed = false;
-    m_capturesDragging = false;
     m_capturingMouseEventsNode = nullptr;
     m_pointerEventManager->clear();
     m_scrollManager->clear();
     m_gestureManager->clear();
     m_mouseEventManager->clear();
-    m_mouseDownMayStartDrag = false;
     m_lastDeferredTapElement = nullptr;
     m_eventHandlerWillResetCapturingMouseEventsNode = false;
-    m_mouseDownMayStartAutoscroll = false;
-    m_svgPan = false;
-    m_mouseDownPos = IntPoint();
-    m_mouseDownTimestamp = 0;
-    m_dragStartPos = LayoutPoint();
-    m_mouseDown = PlatformMouseEvent();
 }
 
 void EventHandler::nodeWillBeRemoved(Node& nodeToBeRemoved)
 {
-    if (nodeToBeRemoved.isShadowIncludingInclusiveAncestorOf(m_clickNode.get())) {
-        // We don't dispatch click events if the mousedown node is removed
-        // before a mouseup event. It is compatible with IE and Firefox.
-        m_clickNode = nullptr;
-    }
-}
-
-WebInputEventResult EventHandler::handleMousePressEvent(const MouseEventWithHitTestResults& event)
-{
-    TRACE_EVENT0("blink", "EventHandler::handleMousePressEvent");
-
-    // Reset drag state.
-    dragState().m_dragSrc = nullptr;
-
-    cancelFakeMouseMoveEvent();
-
-    m_frame->document()->updateStyleAndLayoutIgnorePendingStylesheets();
-
-    if (FrameView* frameView = m_frame->view()) {
-        if (frameView->isPointInScrollbarCorner(event.event().position()))
-            return WebInputEventResult::NotHandled;
-    }
-
-    bool singleClick = event.event().clickCount() <= 1;
-
-    m_mouseDownMayStartDrag = singleClick && !isLinkSelection(event) && !isExtendingSelection(event);
-
-    selectionController().handleMousePressEvent(event);
-
-    m_mouseDown = event.event();
-
-    if (m_frame->document()->isSVGDocument() && m_frame->document()->accessSVGExtensions().zoomAndPanEnabled()) {
-        if (event.event().shiftKey() && singleClick) {
-            m_svgPan = true;
-            m_frame->document()->accessSVGExtensions().startPan(m_frame->view()->rootFrameToContents(event.event().position()));
-            return WebInputEventResult::HandledSystem;
-        }
-    }
-
-    // We don't do this at the start of mouse down handling,
-    // because we don't want to do it until we know we didn't hit a widget.
-    if (singleClick)
-        focusDocumentView();
-
-    Node* innerNode = event.innerNode();
-
-    m_mousePressNode = innerNode;
-    m_frame->document()->setSequentialFocusNavigationStartingPoint(innerNode);
-    m_dragStartPos = event.event().position();
-
-    bool swallowEvent = false;
-    m_mousePressed = true;
-
-    if (event.event().clickCount() == 2)
-        swallowEvent = selectionController().handleMousePressEventDoubleClick(event);
-    else if (event.event().clickCount() >= 3)
-        swallowEvent = selectionController().handleMousePressEventTripleClick(event);
-    else
-        swallowEvent = selectionController().handleMousePressEventSingleClick(event);
-
-    m_mouseDownMayStartAutoscroll = selectionController().mouseDownMayStartSelect()
-        || (m_mousePressNode && m_mousePressNode->layoutBox() && m_mousePressNode->layoutBox()->canBeProgramaticallyScrolled());
-
-    return swallowEvent ? WebInputEventResult::HandledSystem : WebInputEventResult::NotHandled;
-}
-
-WebInputEventResult EventHandler::handleMouseDraggedEvent(const MouseEventWithHitTestResults& event)
-{
-    TRACE_EVENT0("blink", "EventHandler::handleMouseDraggedEvent");
-
-    // While resetting m_mousePressed here may seem out of place, it turns out
-    // to be needed to handle some bugs^Wfeatures in Blink mouse event handling:
-    // 1. Certain elements, such as <embed>, capture mouse events. They do not
-    //    bubble back up. One way for a <embed> to start capturing mouse events
-    //    is on a mouse press. The problem is the <embed> node only starts
-    //    capturing mouse events *after* m_mousePressed for the containing frame
-    //    has already been set to true. As a result, the frame's EventHandler
-    //    never sees the mouse release event, which is supposed to reset
-    //    m_mousePressed... so m_mousePressed ends up remaining true until the
-    //    event handler finally gets another mouse released event. Oops.
-    // 2. Dragging doesn't start until after a mouse press event, but a drag
-    //    that ends as a result of a mouse release does not send a mouse release
-    //    event. As a result, m_mousePressed also ends up remaining true until
-    //    the next mouse release event seen by the EventHandler.
-    if (event.event().pointerProperties().button != WebPointerProperties::Button::Left)
-        m_mousePressed = false;
-
-    if (!m_mousePressed)
-        return WebInputEventResult::NotHandled;
-
-    if (handleDrag(event, DragInitiator::Mouse))
-        return WebInputEventResult::HandledSystem;
-
-    Node* targetNode = event.innerNode();
-    if (!targetNode)
-        return WebInputEventResult::NotHandled;
-
-    LayoutObject* layoutObject = targetNode->layoutObject();
-    if (!layoutObject) {
-        Node* parent = FlatTreeTraversal::parent(*targetNode);
-        if (!parent)
-            return WebInputEventResult::NotHandled;
-
-        layoutObject = parent->layoutObject();
-        if (!layoutObject || !layoutObject->isListBox())
-            return WebInputEventResult::NotHandled;
-    }
-
-    m_mouseDownMayStartDrag = false;
-
-    if (m_mouseDownMayStartAutoscroll && !m_scrollManager->middleClickAutoscrollInProgress()) {
-        if (AutoscrollController* controller = m_scrollManager->autoscrollController()) {
-            controller->startAutoscrollForSelection(layoutObject);
-            m_mouseDownMayStartAutoscroll = false;
-        }
-    }
-
-    selectionController().handleMouseDraggedEvent(event, m_mouseDownPos, m_dragStartPos, m_mousePressNode.get(), m_lastKnownMousePosition);
-    return WebInputEventResult::HandledSystem;
+    m_mouseEventManager->nodeWillBeRemoved(nodeToBeRemoved);
 }
 
 void EventHandler::updateSelectionForMouseDrag()
 {
-    selectionController().updateSelectionForMouseDrag(m_mousePressNode.get(), m_dragStartPos, m_lastKnownMousePosition);
-}
-
-// TODO(nzolghadr): Refactor the mouse related functions to MouseEventManager.
-WebInputEventResult EventHandler::handleMouseReleaseEvent(const MouseEventWithHitTestResults& event)
-{
-    AutoscrollController* controller = m_scrollManager->autoscrollController();
-    if (controller && controller->autoscrollInProgress())
-        m_scrollManager->stopAutoscroll();
-
-    return selectionController().handleMouseReleaseEvent(event, m_dragStartPos) ? WebInputEventResult::HandledSystem : WebInputEventResult::NotHandled;
+    m_mouseEventManager->updateSelectionForMouseDrag();
 }
 
 void EventHandler::startMiddleClickAutoscroll(LayoutObject* layoutObject)
 {
     DCHECK(RuntimeEnabledFeatures::middleClickAutoscrollEnabled());
     if (!layoutObject->isBox())
         return;
     AutoscrollController* controller = m_scrollManager->autoscrollController();
     if (!controller)
         return;
-    controller->startMiddleClickAutoscroll(toLayoutBox(layoutObject), lastKnownMousePosition());
-    invalidateClick();
+    controller->startMiddleClickAutoscroll(toLayoutBox(layoutObject), m_mouseEventManager->lastKnownMousePosition());
+    m_mouseEventManager->invalidateClick();
 }
 
 HitTestResult EventHandler::hitTestResultAtPoint(const LayoutPoint& point, HitTestRequest::HitTestRequestType hitType, const LayoutSize& padding)
 {
     TRACE_EVENT0("blink", "EventHandler::hitTestResultAtPoint");
 
     ASSERT((hitType & HitTestRequest::ListBased) || padding.isEmpty());
 
     // We always send hitTestResultAtPoint to the main frame if we have one,
     // otherwise we might hit areas that are obscured by higher frames.
@@ skipping 11 matching lines @@
 
     // hitTestResultAtPoint is specifically used to hitTest into all frames, thus it always allows child frame content.
     HitTestRequest request(hitType | HitTestRequest::AllowChildFrameContent);
     HitTestResult result(request, point, padding.height().toUnsigned(), padding.width().toUnsigned(), padding.height().toUnsigned(), padding.width().toUnsigned());
 
     // LayoutView::hitTest causes a layout, and we don't want to hit that until the first
     // layout because until then, there is nothing shown on the screen - the user can't
     // have intentionally clicked on something belonging to this page. Furthermore,
     // mousemove events before the first layout should not lead to a premature layout()
     // happening, which could show a flash of white.
-    // See also the similar code in Document::prepareMouseEvent.
+    // See also the similar code in Document::performMouseEventHitTest.
     if (m_frame->contentLayoutItem().isNull() || !m_frame->view() || !m_frame->view()->didFirstLayout())
         return result;
 
     m_frame->contentLayoutItem().hitTest(result);
     if (!request.readOnly())
         m_frame->document()->updateHoverActiveState(request, result.innerElement());
 
     return result;
 }
 
 void EventHandler::stopAutoscroll()
 {
     m_scrollManager->stopAutoscroll();
 }
 
 // TODO(bokan): This should be merged with logicalScroll assuming
 // defaultSpaceEventHandler's chaining scroll can be done crossing frames.
 bool EventHandler::bubblingScroll(ScrollDirection direction, ScrollGranularity granularity, Node* startingNode)
 {
-    return m_scrollManager->bubblingScroll(direction, granularity, startingNode, m_mousePressNode);
+    return m_scrollManager->bubblingScroll(direction, granularity, startingNode, m_mouseEventManager->mousePressNode());
 }
 
 IntPoint EventHandler::lastKnownMousePosition() const
 {
-    return m_lastKnownMousePosition;
+    return m_mouseEventManager->lastKnownMousePosition();
 }
 
 IntPoint EventHandler::dragDataTransferLocationForTesting()
 {
-    if (dragState().m_dragDataTransfer)
-        return dragState().m_dragDataTransfer->dragLocation();
+    if (m_mouseEventManager->dragState().m_dragDataTransfer)
+        return m_mouseEventManager->dragState().m_dragDataTransfer->dragLocation();
 
     return IntPoint();
 }
 
 static LocalFrame* subframeForTargetNode(Node* node)
 {
     if (!node)
         return nullptr;
 
     LayoutObject* layoutObject = node->layoutObject();
@@ skipping 36 matching lines @@
 }
 
 void EventHandler::updateCursor()
 {
     TRACE_EVENT0("input", "EventHandler::updateCursor");
 
     // We must do a cross-frame hit test because the frame that triggered the cursor
     // update could be occluded by a different frame.
     ASSERT(m_frame == m_frame->localFrameRoot());
 
-    if (m_mousePositionIsUnknown)
+    if (m_mouseEventManager->isMousePositionUnknown())
         return;
 
     FrameView* view = m_frame->view();
     if (!view || !view->shouldSetCursor())
         return;
 
     LayoutViewItem layoutViewItem = view->layoutViewItem();
     if (layoutViewItem.isNull())
         return;
 
     m_frame->document()->updateStyleAndLayout();
 
     HitTestRequest request(HitTestRequest::ReadOnly | HitTestRequest::AllowChildFrameContent);
-    HitTestResult result(request, view->rootFrameToContents(m_lastKnownMousePosition));
+    HitTestResult result(request, view->rootFrameToContents(m_mouseEventManager->lastKnownMousePosition()));
     layoutViewItem.hitTest(result);
 
     if (LocalFrame* frame = result.innerNodeFrame()) {
         OptionalCursor optionalCursor = frame->eventHandler().selectCursor(result);
         if (optionalCursor.isCursorChange()) {
             view->setCursor(optionalCursor.cursor());
         }
     }
 }
 
@@ skipping 148 matching lines @@
 
     bool inResizer = false;
     LayoutObject* layoutObject = node ? node->layoutObject() : nullptr;
     if (layoutObject && m_frame->view()) {
         PaintLayer* layer = layoutObject->enclosingLayer();
         inResizer = layer->getScrollableArea() && layer->getScrollableArea()->isPointInResizeControl(result.roundedPointInMainFrame(), ResizerForPointer);
     }
 
     // During selection, use an I-beam no matter what we're over.
     // If a drag may be starting or we're capturing mouse events for a particular node, don't treat this as a selection.
-    if (m_mousePressed && selectionController().mouseDownMayStartSelect()
-        && !m_mouseDownMayStartDrag
+    if (m_mouseEventManager->mousePressed() && selectionController().mouseDownMayStartSelect()
+        && !m_mouseEventManager->mouseDownMayStartDrag()
         && !m_frame->selection().isNone()
         && !m_capturingMouseEventsNode) {
         return iBeam;
     }
 
     if ((editable || (layoutObject && layoutObject->isText() && node->canStartSelection())) && !inResizer && !result.scrollbar())
         return iBeam;
     return pointerCursor();
 }
 
-static LayoutPoint contentPointFromRootFrame(LocalFrame* frame, const IntPoint& pointInRootFrame)
-{
-    FrameView* view = frame->view();
-    // FIXME: Is it really OK to use the wrong coordinates here when view is 0?
-    // Historically the code would just crash; this is clearly no worse than that.
-    return view ? view->rootFrameToContents(pointInRootFrame) : pointInRootFrame;
-}
-
 WebInputEventResult EventHandler::handleMousePressEvent(const PlatformMouseEvent& mouseEvent)
 {
     TRACE_EVENT0("blink", "EventHandler::handleMousePressEvent");
 
     // For 4th/5th button in the mouse since Chrome does not yet send
     // button value to Blink but in some cases it does send the event.
     // This check is needed to suppress such an event (crbug.com/574959)
     if (mouseEvent.pointerProperties().button == WebPointerProperties::Button::NoButton)
         return WebInputEventResult::HandledSuppressed;
 
     UserGestureIndicator gestureIndicator(DefinitelyProcessingUserGesture);
     m_frame->localFrameRoot()->eventHandler().m_lastMouseDownUserGestureToken = UserGestureIndicator::currentToken();
 
-    cancelFakeMouseMoveEvent();
     if (m_eventHandlerWillResetCapturingMouseEventsNode)
         m_capturingMouseEventsNode = nullptr;
-    m_mousePressed = true;
-    m_capturesDragging = true;
-    setLastKnownMousePosition(mouseEvent);
-    m_mouseDownTimestamp = mouseEvent.timestamp();
-    m_mouseDownMayStartDrag = false;
+    m_mouseEventManager->handleMousePressEventUpdateStates(mouseEvent);
     selectionController().setMouseDownMayStartSelect(false);
-    m_mouseDownMayStartAutoscroll = false;
-    if (FrameView* view = m_frame->view()) {
-        m_mouseDownPos = view->rootFrameToContents(mouseEvent.position());
-    } else {
-        invalidateClick();
+
+    if (!m_frame->view())
         return WebInputEventResult::NotHandled;
-    }
 
     HitTestRequest request(HitTestRequest::Active);
     // Save the document point we generate in case the window coordinate is invalidated by what happens
     // when we dispatch the event.
-    LayoutPoint documentPoint = contentPointFromRootFrame(m_frame, mouseEvent.position());
-    MouseEventWithHitTestResults mev = m_frame->document()->prepareMouseEvent(request, documentPoint, mouseEvent);
+    LayoutPoint documentPoint = EventHandlingUtil::contentPointFromRootFrame(m_frame, mouseEvent.position());

[bokan, 2016/09/30 16:57:55]

We don't need this helper method, all it does is null check m_frame->view()
which we've already done above. Just call m_frame->view()->rootFrametoContents
directly.

[Navid Zolghadr, 2016/10/03 16:03:00]

Done.

+    MouseEventWithHitTestResults mev = m_frame->document()->performMouseEventHitTest(request, documentPoint, mouseEvent);
 
     if (!mev.innerNode()) {
-        invalidateClick();
+        m_mouseEventManager->invalidateClick();
         return WebInputEventResult::NotHandled;
     }
 
-    m_mousePressNode = mev.innerNode();
+    m_mouseEventManager->setMousePressNode(mev.innerNode());
     m_frame->document()->setSequentialFocusNavigationStartingPoint(mev.innerNode());
 
     LocalFrame* subframe = subframeForHitTestResult(mev);
     if (subframe) {
         WebInputEventResult result = passMousePressEventToSubframe(mev, subframe);
         // Start capturing future events for this frame.  We only do this if we didn't clear
         // the m_mousePressed flag, which may happen if an AppKit widget entered a modal event loop.
         // The capturing should be done only when the result indicates it
         // has been handled. See crbug.com/269917
-        m_capturesDragging = subframe->eventHandler().capturesDragging();
-        if (m_mousePressed && m_capturesDragging) {
+        m_mouseEventManager->setCapturesDragging(subframe->eventHandler().m_mouseEventManager->capturesDragging());
+        if (m_mouseEventManager->mousePressed() && m_mouseEventManager->capturesDragging()) {
             m_capturingMouseEventsNode = mev.innerNode();
             m_eventHandlerWillResetCapturingMouseEventsNode = true;
         }
-        invalidateClick();
+        m_mouseEventManager->invalidateClick();
         return result;
     }
 
     if (RuntimeEnabledFeatures::middleClickAutoscrollEnabled()) {
         // We store whether middle click autoscroll is in progress before calling stopAutoscroll()
         // because it will set m_autoscrollType to NoAutoscroll on return.
         bool isMiddleClickAutoscrollInProgress = m_scrollManager->middleClickAutoscrollInProgress();
         m_scrollManager->stopAutoscroll();
         if (isMiddleClickAutoscrollInProgress) {
             // We invalidate the click when exiting middle click auto scroll so that we don't inadvertently navigate
             // away from the current page (e.g. the click was on a hyperlink). See <rdar://problem/6095023>.
-            invalidateClick();
+            m_mouseEventManager->invalidateClick();
             return WebInputEventResult::HandledSuppressed;
         }
     }
 
-    m_clickCount = mouseEvent.clickCount();
-    m_clickNode = mev.innerNode()->isTextNode() ?  FlatTreeTraversal::parent(*mev.innerNode()) : mev.innerNode();
+    m_mouseEventManager->setClickCount(mouseEvent.clickCount());
+    m_mouseEventManager->setClickNode(mev.innerNode()->isTextNode() ?  FlatTreeTraversal::parent(*mev.innerNode()) : mev.innerNode());
 
     if (!mouseEvent.fromTouch())
         m_frame->selection().setCaretBlinkingSuspended(true);
 
-    WebInputEventResult eventResult = updatePointerTargetAndDispatchEvents(EventTypeNames::mousedown, mev.innerNode(), m_clickCount, mev.event());
+    WebInputEventResult eventResult = updatePointerTargetAndDispatchEvents(EventTypeNames::mousedown, mev.innerNode(), mev.event());
 
     if (eventResult == WebInputEventResult::NotHandled && m_frame->view()) {
         FrameView* view = m_frame->view();
         PaintLayer* layer = mev.innerNode()->layoutObject() ? mev.innerNode()->layoutObject()->enclosingLayer() : nullptr;
         IntPoint p = view->rootFrameToContents(mouseEvent.position());
         if (layer && layer->getScrollableArea() && layer->getScrollableArea()->isPointInResizeControl(p, ResizerForPointer)) {
             m_scrollManager->setResizeScrollableArea(layer, p);
             return WebInputEventResult::HandledSystem;
         }
     }
 
     // m_selectionInitiationState is initialized after dispatching mousedown
     // event in order not to keep the selection by DOM APIs because we can't
     // give the user the chance to handle the selection by user action like
     // dragging if we keep the selection in case of mousedown. FireFox also has
     // the same behavior and it's more compatible with other browsers.
     selectionController().initializeSelectionState();
     HitTestResult hitTestResult = EventHandlingUtil::hitTestResultInFrame(m_frame, documentPoint, HitTestRequest::ReadOnly);
     InputDeviceCapabilities* sourceCapabilities = mouseEvent.getSyntheticEventType() == PlatformMouseEvent::FromTouch ? InputDeviceCapabilities::firesTouchEventsSourceCapabilities() :
         InputDeviceCapabilities::doesntFireTouchEventsSourceCapabilities();
     if (eventResult == WebInputEventResult::NotHandled)
-        eventResult = handleMouseFocus(hitTestResult, sourceCapabilities);
-    m_capturesDragging = eventResult == WebInputEventResult::NotHandled || mev.scrollbar();
+        eventResult = m_mouseEventManager->handleMouseFocus(hitTestResult, sourceCapabilities);
+    m_mouseEventManager->setCapturesDragging(eventResult == WebInputEventResult::NotHandled || mev.scrollbar());
 
     // If the hit testing originally determined the event was in a scrollbar, refetch the MouseEventWithHitTestResults
     // in case the scrollbar widget was destroyed when the mouse event was handled.
     if (mev.scrollbar()) {
         const bool wasLastScrollBar = mev.scrollbar() == m_lastScrollbarUnderMouse.get();
         HitTestRequest request(HitTestRequest::ReadOnly | HitTestRequest::Active);
-        mev = m_frame->document()->prepareMouseEvent(request, documentPoint, mouseEvent);
+        mev = m_frame->document()->performMouseEventHitTest(request, documentPoint, mouseEvent);
         if (wasLastScrollBar && mev.scrollbar() != m_lastScrollbarUnderMouse.get())
             m_lastScrollbarUnderMouse = nullptr;
     }
 
     if (eventResult != WebInputEventResult::NotHandled) {
         // scrollbars should get events anyway, even disabled controls might be scrollable
         passMousePressEventToScrollbar(mev);
     } else {
         if (shouldRefetchEventTarget(mev)) {
             HitTestRequest request(HitTestRequest::ReadOnly | HitTestRequest::Active);
-            mev = m_frame->document()->prepareMouseEvent(request, documentPoint, mouseEvent);
+            mev = m_frame->document()->performMouseEventHitTest(request, documentPoint, mouseEvent);
         }
 
         if (passMousePressEventToScrollbar(mev))
             eventResult = WebInputEventResult::HandledSystem;
         else
-            eventResult = handleMousePressEvent(mev);
+            eventResult = m_mouseEventManager->handleMousePressEvent(mev);
     }
 
     if (mev.hitTestResult().innerNode() && mouseEvent.pointerProperties().button == WebPointerProperties::Button::Left) {
         ASSERT(mouseEvent.type() == PlatformEvent::MousePressed);
         HitTestResult result = mev.hitTestResult();
         result.setToShadowHostIfInUserAgentShadowRoot();
         m_frame->chromeClient().onMouseDown(result.innerNode());
     }
 
     return eventResult;
 }
 
-static PaintLayer* layerForNode(Node* node)
-{
-    if (!node)
-        return nullptr;
-
-    LayoutObject* layoutObject = node->layoutObject();
-    if (!layoutObject)
-        return nullptr;
-
-    PaintLayer* layer = layoutObject->enclosingLayer();
-    if (!layer)
-        return nullptr;
-
-    return layer;
-}
-
-ScrollableArea* EventHandler::associatedScrollableArea(const PaintLayer* layer) const
-{
-    if (PaintLayerScrollableArea* scrollableArea = layer->getScrollableArea()) {
-        if (scrollableArea->scrollsOverflow())
-            return scrollableArea;
-    }
-
-    return nullptr;
-}
-
 WebInputEventResult EventHandler::handleMouseMoveEvent(const PlatformMouseEvent& event)
 {
     TRACE_EVENT0("blink", "EventHandler::handleMouseMoveEvent");
 
     HitTestResult hoveredNode = HitTestResult();
     WebInputEventResult result = handleMouseMoveOrLeaveEvent(event, &hoveredNode);
 
     Page* page = m_frame->page();
     if (!page)
         return result;
 
-    if (PaintLayer* layer = layerForNode(hoveredNode.innerNode())) {
-        if (ScrollableArea* layerScrollableArea = associatedScrollableArea(layer))
+    if (PaintLayer* layer = EventHandlingUtil::layerForNode(hoveredNode.innerNode())) {
+        if (ScrollableArea* layerScrollableArea = EventHandlingUtil::associatedScrollableArea(layer))
             layerScrollableArea->mouseMovedInContentArea();
     }
 
     if (FrameView* frameView = m_frame->view())
         frameView->mouseMovedInContentArea();
 
     hoveredNode.setToShadowHostIfInUserAgentShadowRoot();
     page->chromeClient().mouseDidMoveOverElement(hoveredNode);
 
     return result;
 }
 
 void EventHandler::handleMouseLeaveEvent(const PlatformMouseEvent& event)
 {
     TRACE_EVENT0("blink", "EventHandler::handleMouseLeaveEvent");
 
     handleMouseMoveOrLeaveEvent(event, 0, false, true);
 }
 
 WebInputEventResult EventHandler::handleMouseMoveOrLeaveEvent(const PlatformMouseEvent& mouseEvent, HitTestResult* hoveredNode, bool onlyUpdateScrollbars, bool forceLeave)
 {
     ASSERT(m_frame);
     ASSERT(m_frame->view());
 
-    setLastKnownMousePosition(mouseEvent);
+    m_mouseEventManager->setLastKnownMousePosition(mouseEvent);
 
     if (m_hoverTimer.isActive())
         m_hoverTimer.stop();
 
     m_cursorUpdateTimer.stop();
 
-    cancelFakeMouseMoveEvent();
+    m_mouseEventManager->cancelFakeMouseMoveEvent();
 
-    if (m_svgPan) {
-        m_frame->document()->accessSVGExtensions().updatePan(m_frame->view()->rootFrameToContents(m_lastKnownMousePosition));
-        return WebInputEventResult::HandledSuppressed;
-    }
+    m_mouseEventManager->handleSvgPanIfNeeded(false);
 
     if (m_frameSetBeingResized)
-        return updatePointerTargetAndDispatchEvents(EventTypeNames::mousemove, m_frameSetBeingResized.get(), 0, mouseEvent);
+        return updatePointerTargetAndDispatchEvents(EventTypeNames::mousemove, m_frameSetBeingResized.get(), mouseEvent);
 
     // Send events right to a scrollbar if the mouse is pressed.
-    if (m_lastScrollbarUnderMouse && m_mousePressed) {
+    if (m_lastScrollbarUnderMouse && m_mouseEventManager->mousePressed()) {
         m_lastScrollbarUnderMouse->mouseMoved(mouseEvent);
         return WebInputEventResult::HandledSystem;
     }
 
     // Mouse events simulated from touch should not hit-test again.
     ASSERT(!mouseEvent.fromTouch());
 
     HitTestRequest::HitTestRequestType hitType = HitTestRequest::Move;
-    if (m_mousePressed) {
+    if (m_mouseEventManager->mousePressed()) {
         hitType |= HitTestRequest::Active;
     } else if (onlyUpdateScrollbars) {
         // Mouse events should be treated as "read-only" if we're updating only scrollbars. This
         // means that :hover and :active freeze in the state they were in, rather than updating
         // for nodes the mouse moves while the window is not key (which will be the case if
         // onlyUpdateScrollbars is true).
         hitType |= HitTestRequest::ReadOnly;
     }
 
     // Treat any mouse move events as readonly if the user is currently touching the screen.
     if (m_pointerEventManager->isAnyTouchActive())
         hitType |= HitTestRequest::Active | HitTestRequest::ReadOnly;
     HitTestRequest request(hitType);
     MouseEventWithHitTestResults mev = MouseEventWithHitTestResults(mouseEvent, HitTestResult(request, LayoutPoint()));
 
     // We don't want to do a hit-test in forceLeave scenarios because there might actually be some other frame above this one at the specified co-ordinate.
     // So we must force the hit-test to fail, while still clearing hover/active state.
     if (forceLeave)
         m_frame->document()->updateHoverActiveState(request, 0);
     else
-        mev = prepareMouseEvent(request, mouseEvent);
+        mev = EventHandlingUtil::performMouseEventHitTest(m_frame, request, mouseEvent);
 
     if (hoveredNode)
         *hoveredNode = mev.hitTestResult();
 
     Scrollbar* scrollbar = nullptr;
 
     if (m_scrollManager->inResizeMode()) {
         m_scrollManager->resize(mev.event());
     } else {
         if (!scrollbar)
             scrollbar = mev.scrollbar();
 
-        updateLastScrollbarUnderMouse(scrollbar, !m_mousePressed);
+        updateLastScrollbarUnderMouse(scrollbar, !m_mouseEventManager->mousePressed());
         if (onlyUpdateScrollbars)
             return WebInputEventResult::HandledSuppressed;
     }
 
     WebInputEventResult eventResult = WebInputEventResult::NotHandled;
     LocalFrame* newSubframe = m_capturingMouseEventsNode.get() ? subframeForTargetNode(m_capturingMouseEventsNode.get()) : subframeForHitTestResult(mev);
 
     // We want mouseouts to happen first, from the inside out.  First send a move event to the last subframe so that it will fire mouseouts.
     if (m_lastMouseMoveEventSubframe && m_lastMouseMoveEventSubframe->tree().isDescendantOf(m_frame) && m_lastMouseMoveEventSubframe != newSubframe)
         m_lastMouseMoveEventSubframe->eventHandler().handleMouseLeaveEvent(mev.event());
 
     if (newSubframe) {
         // Update over/out state before passing the event to the subframe.
-        updateMouseEventTargetNodeAndSendEvents(mev.innerNode(), mev.event(), true);
+        m_pointerEventManager->sendMouseAndPointerBoundaryEvents(updateMouseEventTargetNode(mev.innerNode()), mev.event());
 
-        // Event dispatch in updateMouseEventTargetNodeAndSendEvents may have caused the subframe of the target
+        // Event dispatch in sendMouseAndPointerBoundaryEvents may have caused the subframe of the target
         // node to be detached from its FrameView, in which case the event should not be passed.
         if (newSubframe->view())
             eventResult = passMouseMoveEventToSubframe(mev, newSubframe, hoveredNode);
     } else {
-        if (scrollbar && !m_mousePressed)
+        if (scrollbar && !m_mouseEventManager->mousePressed())
             scrollbar->mouseMoved(mev.event()); // Handle hover effects on platforms that support visual feedback on scrollbar hovering.
         if (FrameView* view = m_frame->view()) {
             OptionalCursor optionalCursor = selectCursor(mev.hitTestResult());
             if (optionalCursor.isCursorChange()) {
                 view->setCursor(optionalCursor.cursor());
             }
         }
     }
 
     m_lastMouseMoveEventSubframe = newSubframe;
 
     if (eventResult != WebInputEventResult::NotHandled)
         return eventResult;
 
-    eventResult = updatePointerTargetAndDispatchEvents(EventTypeNames::mousemove, mev.innerNode(), 0, mev.event());
+    eventResult = updatePointerTargetAndDispatchEvents(EventTypeNames::mousemove, mev.innerNode(), mev.event());
     if (eventResult != WebInputEventResult::NotHandled)
         return eventResult;
 
-    return handleMouseDraggedEvent(mev);
-}
-
-void EventHandler::invalidateClick()
-{
-    m_clickCount = 0;
-    m_clickNode = nullptr;
-}
-
-ContainerNode* EventHandler::parentForClickEvent(const Node& node)
-{
-    // IE doesn't dispatch click events for mousedown/mouseup events across form
-    // controls.
-    if (node.isHTMLElement() && toHTMLElement(node).isInteractiveContent())
-        return nullptr;
-
-    return FlatTreeTraversal::parent(node);
+    return m_mouseEventManager->handleMouseDraggedEvent(mev);
 }
 
 WebInputEventResult EventHandler::handleMouseReleaseEvent(const PlatformMouseEvent& mouseEvent)
 {
     TRACE_EVENT0("blink", "EventHandler::handleMouseReleaseEvent");
 
     // For 4th/5th button in the mouse since Chrome does not yet send
     // button value to Blink but in some cases it does send the event.
     // This check is needed to suppress such an event (crbug.com/574959)
     if (mouseEvent.pointerProperties().button == WebPointerProperties::Button::NoButton)
         return WebInputEventResult::HandledSuppressed;
 
     if (!mouseEvent.fromTouch())
         m_frame->selection().setCaretBlinkingSuspended(false);
 
     std::unique_ptr<UserGestureIndicator> gestureIndicator;
 
     if (m_frame->localFrameRoot()->eventHandler().m_lastMouseDownUserGestureToken)
         gestureIndicator = wrapUnique(new UserGestureIndicator(m_frame->localFrameRoot()->eventHandler().m_lastMouseDownUserGestureToken.release()));
     else
         gestureIndicator = wrapUnique(new UserGestureIndicator(DefinitelyProcessingUserGesture));
 
     if (RuntimeEnabledFeatures::middleClickAutoscrollEnabled()) {
         if (Page* page = m_frame->page())
             page->autoscrollController().handleMouseReleaseForMiddleClickAutoscroll(m_frame, mouseEvent);
     }
 
-    m_mousePressed = false;
-    setLastKnownMousePosition(mouseEvent);
-
-    if (m_svgPan) {
-        m_svgPan = false;
-        m_frame->document()->accessSVGExtensions().updatePan(m_frame->view()->rootFrameToContents(m_lastKnownMousePosition));
-        return WebInputEventResult::HandledSuppressed;
-    }
+    m_mouseEventManager->setMousePressed(false);
+    m_mouseEventManager->setLastKnownMousePosition(mouseEvent);
+    m_mouseEventManager->handleSvgPanIfNeeded(true);
 
     if (m_frameSetBeingResized)
-        return dispatchMouseEvent(EventTypeNames::mouseup, m_frameSetBeingResized.get(), m_clickCount, mouseEvent);
+        return m_mouseEventManager->setMousePositionAndDispatchMouseEvent(updateMouseEventTargetNode(m_frameSetBeingResized.get()), EventTypeNames::mouseup, mouseEvent);
 
     if (m_lastScrollbarUnderMouse) {
-        invalidateClick();
+        m_mouseEventManager->invalidateClick();
         m_lastScrollbarUnderMouse->mouseUp(mouseEvent);
-        return updatePointerTargetAndDispatchEvents(EventTypeNames::mouseup, m_nodeUnderMouse.get(), m_clickCount, mouseEvent);
+        return updatePointerTargetAndDispatchEvents(EventTypeNames::mouseup, m_mouseEventManager->getNodeUnderMouse(), mouseEvent);
     }
 
     // Mouse events simulated from touch should not hit-test again.
     ASSERT(!mouseEvent.fromTouch());
 
     HitTestRequest::HitTestRequestType hitType = HitTestRequest::Release;
     HitTestRequest request(hitType);
-    MouseEventWithHitTestResults mev = prepareMouseEvent(request, mouseEvent);
+    MouseEventWithHitTestResults mev = EventHandlingUtil::performMouseEventHitTest(m_frame, request, mouseEvent);
     LocalFrame* subframe = m_capturingMouseEventsNode.get() ? subframeForTargetNode(m_capturingMouseEventsNode.get()) : subframeForHitTestResult(mev);
     if (m_eventHandlerWillResetCapturingMouseEventsNode)
         m_capturingMouseEventsNode = nullptr;
     if (subframe)
         return passMouseReleaseEventToSubframe(mev, subframe);
 
-    WebInputEventResult eventResult = updatePointerTargetAndDispatchEvents(EventTypeNames::mouseup, mev.innerNode(), m_clickCount, mev.event());
+    WebInputEventResult eventResult = updatePointerTargetAndDispatchEvents(EventTypeNames::mouseup, mev.innerNode(), mev.event());
 
-    // We only prevent click event when the click may cause contextmenu to popup.
-    // However, we always send auxclick.
-    bool contextMenuEvent = !RuntimeEnabledFeatures::auxclickEnabled()
-        && mouseEvent.pointerProperties().button == WebPointerProperties::Button::Right;
-#if OS(MACOSX)
-    // FIXME: The Mac port achieves the same behavior by checking whether the context menu is currently open in WebPage::mouseEvent(). Consider merging the implementations.
-    if (mouseEvent.pointerProperties().button == WebPointerProperties::Button::Left
-        && mouseEvent.getModifiers() & PlatformEvent::CtrlKey)
-        contextMenuEvent = true;
-#endif
-
-    WebInputEventResult clickEventResult = WebInputEventResult::NotHandled;
-    const bool shouldDispatchClickEvent = m_clickCount > 0
-        && !contextMenuEvent
-        && mev.innerNode() && m_clickNode
-        && mev.innerNode()->canParticipateInFlatTree() && m_clickNode->canParticipateInFlatTree()
-        && !(selectionController().hasExtendedSelection() && isLinkSelection(mev));
-    if (shouldDispatchClickEvent) {
-        Node* clickTargetNode = nullptr;
-        // Updates distribution because a 'mouseup' event listener can make the
-        // tree dirty at dispatchMouseEvent() invocation above.
-        // Unless distribution is updated, commonAncestor would hit ASSERT.
-        if (m_clickNode == mev.innerNode()) {
-            clickTargetNode = m_clickNode;
-            clickTargetNode->updateDistribution();
-        } else if (m_clickNode->document() == mev.innerNode()->document()) {
-            m_clickNode->updateDistribution();
-            mev.innerNode()->updateDistribution();
-            clickTargetNode = mev.innerNode()->commonAncestor(
-                *m_clickNode, parentForClickEvent);
-        }
-        if (clickTargetNode) {
-            // Dispatch mouseup directly w/o calling updateMouseEventTargetNodeAndSendEvents
-            // because the mouseup dispatch above has already updated it
-            // correctly. Moreover, clickTargetNode is different from
-            // mev.innerNode at drag-release.
-            clickEventResult = EventHandlingUtil::toWebInputEventResult(
-                clickTargetNode->dispatchMouseEvent(mev.event(),
-                    !RuntimeEnabledFeatures::auxclickEnabled()
-                    || (mev.event().pointerProperties().button == WebPointerProperties::Button::Left)
-                        ? EventTypeNames::click
-                        : EventTypeNames::auxclick,
-                    m_clickCount));
-        }
-    }
-
+    WebInputEventResult clickEventResult = m_mouseEventManager->dispatchMouseClickIfNeeded(mev);
     m_scrollManager->clearResizeScrollableArea(false);
 
     if (eventResult == WebInputEventResult::NotHandled)
-        eventResult = handleMouseReleaseEvent(mev);
-    clearDragHeuristicState();
+        eventResult = m_mouseEventManager->handleMouseReleaseEvent(mev);
+    m_mouseEventManager->clearDragHeuristicState();
 
-    invalidateClick();
+    m_mouseEventManager->invalidateClick();
 
     return EventHandlingUtil::mergeEventResult(clickEventResult, eventResult);
 }
 
-WebInputEventResult EventHandler::dispatchDragEvent(const AtomicString& eventType, Node* dragTarget, const PlatformMouseEvent& event, DataTransfer* dataTransfer)
-{
-    FrameView* view = m_frame->view();
-
-    // FIXME: We might want to dispatch a dragleave even if the view is gone.
-    if (!view)
-        return WebInputEventResult::NotHandled;
-
-    DragEvent* me = DragEvent::create(eventType,
-        true, true, m_frame->document()->domWindow(),
-        0, event.globalPosition().x(), event.globalPosition().y(), event.position().x(), event.position().y(),
-        event.movementDelta().x(), event.movementDelta().y(),
-        event.getModifiers(),
-        0, MouseEvent::platformModifiersToButtons(event.getModifiers()), nullptr, event.timestamp(), dataTransfer, event.getSyntheticEventType());
-
-    return EventHandlingUtil::toWebInputEventResult(dragTarget->dispatchEvent(me));
-}
-
 static bool targetIsFrame(Node* target, LocalFrame*& frame)
 {
     if (!isHTMLFrameElementBase(target))
         return false;
 
     // Cross-process drag and drop is not yet supported.
     if (toHTMLFrameElementBase(target)->contentFrame() && !toHTMLFrameElementBase(target)->contentFrame()->isLocalFrame())
         return false;
 
     frame = toLocalFrame(toHTMLFrameElementBase(target)->contentFrame());
@@ skipping 40 matching lines @@
 }
 
 WebInputEventResult EventHandler::updateDragAndDrop(const PlatformMouseEvent& event, DataTransfer* dataTransfer)
 {
     WebInputEventResult eventResult = WebInputEventResult::NotHandled;
 
     if (!m_frame->view())
         return eventResult;
 
     HitTestRequest request(HitTestRequest::ReadOnly);
-    MouseEventWithHitTestResults mev = prepareMouseEvent(request, event);
+    MouseEventWithHitTestResults mev = EventHandlingUtil::performMouseEventHitTest(m_frame, request, event);
 
     // Drag events should never go to text nodes (following IE, and proper mouseover/out dispatch)
     Node* newTarget = mev.innerNode();
     if (newTarget && newTarget->isTextNode())
         newTarget = FlatTreeTraversal::parent(*newTarget);
 
     if (AutoscrollController* controller = m_scrollManager->autoscrollController())
         controller->updateDragAndDrop(newTarget, event.position(), event.timestamp());
 
     if (m_dragTarget != newTarget) {
         // FIXME: this ordering was explicitly chosen to match WinIE. However,
         // it is sometimes incorrect when dragging within subframes, as seen with
         // LayoutTests/fast/events/drag-in-frames.html.
         //
         // Moreover, this ordering conforms to section 7.9.4 of the HTML 5 spec. <http://dev.w3.org/html5/spec/Overview.html#drag-and-drop-processing-model>.
         LocalFrame* targetFrame;
         if (targetIsFrame(newTarget, targetFrame)) {
             if (targetFrame)
                 eventResult = targetFrame->eventHandler().updateDragAndDrop(event, dataTransfer);
         } else if (newTarget) {
             // As per section 7.9.4 of the HTML 5 spec., we must always fire a drag event before firing a dragenter, dragleave, or dragover event.
-            if (dragState().m_dragSrc) {
+            if (m_mouseEventManager->dragState().m_dragSrc) {
                 // for now we don't care if event handler cancels default behavior, since there is none
-                dispatchDragSrcEvent(EventTypeNames::drag, event);
+                m_mouseEventManager->dispatchDragSrcEvent(EventTypeNames::drag, event);
             }
-            eventResult = dispatchDragEvent(EventTypeNames::dragenter, newTarget, event, dataTransfer);
+            eventResult = m_mouseEventManager->dispatchDragEvent(EventTypeNames::dragenter, newTarget, event, dataTransfer);
             if (eventResult == WebInputEventResult::NotHandled && findDropZone(newTarget, dataTransfer))
                 eventResult = WebInputEventResult::HandledSystem;
         }
 
         if (targetIsFrame(m_dragTarget.get(), targetFrame)) {
             if (targetFrame)
                 eventResult = targetFrame->eventHandler().updateDragAndDrop(event, dataTransfer);
         } else if (m_dragTarget) {
-            dispatchDragEvent(EventTypeNames::dragleave, m_dragTarget.get(), event, dataTransfer);
+            m_mouseEventManager->dispatchDragEvent(EventTypeNames::dragleave, m_dragTarget.get(), event, dataTransfer);
         }
 
         if (newTarget) {
-            // We do not explicitly call dispatchDragEvent here because it could ultimately result in the appearance that
+            // We do not explicitly call m_mouseEventManager->dispatchDragEvent here because it could ultimately result in the appearance that
             // two dragover events fired. So, we mark that we should only fire a dragover event on the next call to this function.
             m_shouldOnlyFireDragOverEvent = true;
         }
     } else {
         LocalFrame* targetFrame;
         if (targetIsFrame(newTarget, targetFrame)) {
             if (targetFrame)
                 eventResult = targetFrame->eventHandler().updateDragAndDrop(event, dataTransfer);
         } else if (newTarget) {
             // Note, when dealing with sub-frames, we may need to fire only a dragover event as a drag event may have been fired earlier.
-            if (!m_shouldOnlyFireDragOverEvent && dragState().m_dragSrc) {
+            if (!m_shouldOnlyFireDragOverEvent && m_mouseEventManager->dragState().m_dragSrc) {
                 // for now we don't care if event handler cancels default behavior, since there is none
-                dispatchDragSrcEvent(EventTypeNames::drag, event);
+                m_mouseEventManager->dispatchDragSrcEvent(EventTypeNames::drag, event);
             }
-            eventResult = dispatchDragEvent(EventTypeNames::dragover, newTarget, event, dataTransfer);
+            eventResult = m_mouseEventManager->dispatchDragEvent(EventTypeNames::dragover, newTarget, event, dataTransfer);
             if (eventResult == WebInputEventResult::NotHandled && findDropZone(newTarget, dataTransfer))
                 eventResult = WebInputEventResult::HandledSystem;
             m_shouldOnlyFireDragOverEvent = false;
         }
     }
     m_dragTarget = newTarget;
 
     return eventResult;
 }
 
 void EventHandler::cancelDragAndDrop(const PlatformMouseEvent& event, DataTransfer* dataTransfer)
 {
     LocalFrame* targetFrame;
     if (targetIsFrame(m_dragTarget.get(), targetFrame)) {
         if (targetFrame)
             targetFrame->eventHandler().cancelDragAndDrop(event, dataTransfer);
     } else if (m_dragTarget.get()) {
-        if (dragState().m_dragSrc)
-            dispatchDragSrcEvent(EventTypeNames::drag, event);
-        dispatchDragEvent(EventTypeNames::dragleave, m_dragTarget.get(), event, dataTransfer);
+        if (m_mouseEventManager->dragState().m_dragSrc)
+            m_mouseEventManager->dispatchDragSrcEvent(EventTypeNames::drag, event);
+        m_mouseEventManager->dispatchDragEvent(EventTypeNames::dragleave, m_dragTarget.get(), event, dataTransfer);
     }
     clearDragState();
 }
 
 WebInputEventResult EventHandler::performDragAndDrop(const PlatformMouseEvent& event, DataTransfer* dataTransfer)
 {
     LocalFrame* targetFrame;
     WebInputEventResult result = WebInputEventResult::NotHandled;
     if (targetIsFrame(m_dragTarget.get(), targetFrame)) {
         if (targetFrame)
             result = targetFrame->eventHandler().performDragAndDrop(event, dataTransfer);
     } else if (m_dragTarget.get()) {
-        result = dispatchDragEvent(EventTypeNames::drop, m_dragTarget.get(), event, dataTransfer);
+        result = m_mouseEventManager->dispatchDragEvent(EventTypeNames::drop, m_dragTarget.get(), event, dataTransfer);
     }
     clearDragState();
     return result;
 }
 
-void EventHandler::clearDragHeuristicState()
-{
-    // Used to prevent mouseMoveEvent from initiating a drag before
-    // the mouse is pressed again.
-    m_mousePressed = false;
-    m_capturesDragging = false;
-    m_mouseDownMayStartDrag = false;
-    m_mouseDownMayStartAutoscroll = false;
-}
-
 void EventHandler::clearDragState()
 {
     m_scrollManager->stopAutoscroll();
     m_dragTarget = nullptr;
     m_capturingMouseEventsNode = nullptr;
     m_shouldOnlyFireDragOverEvent = false;
 }
 
 void EventHandler::setCapturingMouseEventsNode(Node* n)
 {
     m_capturingMouseEventsNode = n;
     m_eventHandlerWillResetCapturingMouseEventsNode = false;
 }
 
-MouseEventWithHitTestResults EventHandler::prepareMouseEvent(const HitTestRequest& request, const PlatformMouseEvent& mev)
-{
-    ASSERT(m_frame);
-    ASSERT(m_frame->document());
-
-    return m_frame->document()->prepareMouseEvent(request, contentPointFromRootFrame(m_frame, mev.position()), mev);
-}
-
-Node* EventHandler::updateMouseEventTargetNode(Node* targetNode,
-    const PlatformMouseEvent& mouseEvent)
+Node* EventHandler::updateMouseEventTargetNode(Node* targetNode)
 {
     Node* newNodeUnderMouse = targetNode;
 
     // If we're capturing, we always go right to that node.
     EventTarget* mousePointerCapturingNode = m_pointerEventManager->getMouseCapturingNode();
     if (mousePointerCapturingNode
         && !RuntimeEnabledFeatures::pointerEventV1SpecCapturingEnabled()) {
         newNodeUnderMouse = mousePointerCapturingNode->toNode();
         DCHECK(newNodeUnderMouse);
     } else if (m_capturingMouseEventsNode) {
         newNodeUnderMouse = m_capturingMouseEventsNode.get();
     } else {
         // If the target node is a text node, dispatch on the parent node - rdar://4196646
         if (newNodeUnderMouse && newNodeUnderMouse->isTextNode())
             newNodeUnderMouse = FlatTreeTraversal::parent(*newNodeUnderMouse);
     }
-    Node* lastNodeUnderMouse = m_nodeUnderMouse;
-    m_nodeUnderMouse = newNodeUnderMouse;
-
-    PaintLayer* layerForLastNode = layerForNode(lastNodeUnderMouse);
-    PaintLayer* layerForNodeUnderMouse = layerForNode(m_nodeUnderMouse.get());
-    Page* page = m_frame->page();
-
-    if (lastNodeUnderMouse && (!m_nodeUnderMouse || m_nodeUnderMouse->document() != m_frame->document())) {
-        // The mouse has moved between frames.
-        if (LocalFrame* frame = lastNodeUnderMouse->document().frame()) {
-            if (FrameView* frameView = frame->view())
-                frameView->mouseExitedContentArea();
-        }
-    } else if (page && (layerForLastNode && (!layerForNodeUnderMouse || layerForNodeUnderMouse != layerForLastNode))) {
-        // The mouse has moved between layers.
-        if (ScrollableArea* scrollableAreaForLastNode = associatedScrollableArea(layerForLastNode))
-            scrollableAreaForLastNode->mouseExitedContentArea();
-    }
-
-    if (m_nodeUnderMouse && (!lastNodeUnderMouse || lastNodeUnderMouse->document() != m_frame->document())) {
-        // The mouse has moved between frames.
-        if (LocalFrame* frame = m_nodeUnderMouse->document().frame()) {
-            if (FrameView* frameView = frame->view())
-                frameView->mouseEnteredContentArea();
-        }
-    } else if (page && (layerForNodeUnderMouse && (!layerForLastNode || layerForNodeUnderMouse != layerForLastNode))) {
-        // The mouse has moved between layers.
-        if (ScrollableArea* scrollableAreaForNodeUnderMouse = associatedScrollableArea(layerForNodeUnderMouse))
-            scrollableAreaForNodeUnderMouse->mouseEnteredContentArea();
-    }
-
-    if (lastNodeUnderMouse && lastNodeUnderMouse->document() != m_frame->document()) {
-        lastNodeUnderMouse = nullptr;
-        m_lastScrollbarUnderMouse = nullptr;
-    }
-
-    return lastNodeUnderMouse;
-}
-
-void EventHandler::updateMouseEventTargetNodeAndSendEvents(Node* targetNode,
-    const PlatformMouseEvent& mouseEvent, bool isFrameBoundaryTransition)
-{
-    Node* lastNodeUnderMouse = updateMouseEventTargetNode(targetNode, mouseEvent);
-    m_pointerEventManager->sendMouseAndPossiblyPointerBoundaryEvents(
-        lastNodeUnderMouse, m_nodeUnderMouse, mouseEvent,
-        isFrameBoundaryTransition);
-}
-
-WebInputEventResult EventHandler::dispatchMouseEvent(const AtomicString& eventType, Node* targetNode, int clickCount, const PlatformMouseEvent& mouseEvent)
-{
-    updateMouseEventTargetNodeAndSendEvents(targetNode, mouseEvent);
-
-    return m_mouseEventManager->dispatchMouseEvent(m_nodeUnderMouse, eventType,
-        mouseEvent, nullptr, clickCount);
+    return newNodeUnderMouse;
 }
 
 bool EventHandler::isPointerEventActive(int pointerId)
 {
     return m_pointerEventManager->isActive(pointerId);
 }
 
 void EventHandler::setPointerCapture(int pointerId, EventTarget* target)
 {
     // TODO(crbug.com/591387): This functionality should be per page not per frame.
@@ skipping 13 matching lines @@
 bool EventHandler::hasProcessedPointerCapture(int pointerId, const EventTarget* target) const
 {
     return m_pointerEventManager->hasProcessedPointerCapture(pointerId, target);
 }
 
 void EventHandler::elementRemoved(EventTarget* target)
 {
     m_pointerEventManager->elementRemoved(target);
 }
 
-// TODO(mustaq): Make PE drive ME dispatch & bookkeeping in EventHandler.
-WebInputEventResult EventHandler::updatePointerTargetAndDispatchEvents(const AtomicString& mouseEventType, Node* targetNode, int clickCount, const PlatformMouseEvent& mouseEvent)
+WebInputEventResult EventHandler::updatePointerTargetAndDispatchEvents(const AtomicString& mouseEventType, Node* targetNode, const PlatformMouseEvent& mouseEvent)
 {
     ASSERT(mouseEventType == EventTypeNames::mousedown
         || mouseEventType == EventTypeNames::mousemove
         || mouseEventType == EventTypeNames::mouseup);
 
-    Node* lastNodeUnderMouse = updateMouseEventTargetNode(targetNode, mouseEvent);
-
-    Node* newNodeUnderMouse = nullptr;
     const auto& eventResult = m_pointerEventManager->sendMousePointerEvent(
-        m_nodeUnderMouse, mouseEventType, clickCount, mouseEvent,
-        lastNodeUnderMouse, &newNodeUnderMouse);
-    m_nodeUnderMouse = newNodeUnderMouse;
+        updateMouseEventTargetNode(targetNode), mouseEventType, mouseEvent);
     return eventResult;
 }
 
-void EventHandler::setClickNode(Node* node)
-{
-    m_clickNode = node;
-}
-
-WebInputEventResult EventHandler::handleMouseFocus(const HitTestResult& hitTestResult, InputDeviceCapabilities* sourceCapabilities)
-{
-    // If clicking on a frame scrollbar, do not mess up with content focus.
-    if (hitTestResult.scrollbar() && !m_frame->contentLayoutItem().isNull()) {
-        if (hitTestResult.scrollbar()->getScrollableArea() == m_frame->contentLayoutItem().getScrollableArea())
-            return WebInputEventResult::NotHandled;
-    }
-
-    // The layout needs to be up to date to determine if an element is focusable.
-    m_frame->document()->updateStyleAndLayoutIgnorePendingStylesheets();
-
-    Element* element = nullptr;
-    if (m_nodeUnderMouse)
-        element = m_nodeUnderMouse->isElementNode() ? toElement(m_nodeUnderMouse) : m_nodeUnderMouse->parentOrShadowHostElement();
-    for (; element; element = element->parentOrShadowHostElement()) {
-        if (element->isFocusable() && element->isFocusedElementInDocument())
-            return WebInputEventResult::NotHandled;
-        if (element->isMouseFocusable())
-            break;
-    }
-    ASSERT(!element || element->isMouseFocusable());
-
-    // To fix <rdar://problem/4895428> Can't drag selected ToDo, we don't focus
-    // a node on mouse down if it's selected and inside a focused node. It will
-    // be focused if the user does a mouseup over it, however, because the
-    // mouseup will set a selection inside it, which will call
-    // FrameSelection::setFocusedNodeIfNeeded.
-    if (element && m_frame->selection().isRange()) {
-        // TODO(yosin) We should not create |Range| object for calling
-        // |isNodeFullyContained()|.
-        if (createRange(m_frame->selection().selection().toNormalizedEphemeralRange())->isNodeFullyContained(*element)
-            && element->isDescendantOf(m_frame->document()->focusedElement()))
-            return WebInputEventResult::NotHandled;
-    }
-
-
-    // Only change the focus when clicking scrollbars if it can transfered to a
-    // mouse focusable node.
-    if (!element && hitTestResult.scrollbar())
-        return WebInputEventResult::HandledSystem;
-
-    if (Page* page = m_frame->page()) {
-        // If focus shift is blocked, we eat the event. Note we should never
-        // clear swallowEvent if the page already set it (e.g., by canceling
-        // default behavior).
-        if (element) {
-            if (slideFocusOnShadowHostIfNecessary(*element))
-                return WebInputEventResult::HandledSystem;
-            if (!page->focusController().setFocusedElement(element, m_frame, FocusParams(SelectionBehaviorOnFocus::None, WebFocusTypeMouse, sourceCapabilities)))
-                return WebInputEventResult::HandledSystem;
-        } else {
-            // We call setFocusedElement even with !element in order to blur
-            // current focus element when a link is clicked; this is expected by
-            // some sites that rely on onChange handlers running from form
-            // fields before the button click is processed.
-            if (!page->focusController().setFocusedElement(nullptr, m_frame, FocusParams(SelectionBehaviorOnFocus::None, WebFocusTypeNone, sourceCapabilities)))
-                return WebInputEventResult::HandledSystem;
-        }
-    }
-
-    return WebInputEventResult::NotHandled;
-}
-
-bool EventHandler::slideFocusOnShadowHostIfNecessary(const Element& element)
-{
-    if (element.authorShadowRoot() && element.authorShadowRoot()->delegatesFocus()) {
-        Document* doc = m_frame->document();
-        if (element.isShadowIncludingInclusiveAncestorOf(doc->focusedElement())) {
-            // If the inner element is already focused, do nothing.
-            return true;
-        }
-
-        // If the host has a focusable inner element, focus it. Otherwise, the host takes focus.
-        Page* page = m_frame->page();
-        ASSERT(page);
-        Element* found = page->focusController().findFocusableElementInShadowHost(element);
-        if (found && element.isShadowIncludingInclusiveAncestorOf(found)) {
-            // Use WebFocusTypeForward instead of WebFocusTypeMouse here to mean the focus has slided.
-            found->focus(FocusParams(SelectionBehaviorOnFocus::Reset, WebFocusTypeForward, nullptr));
-            return true;
-        }
-    }
-    return false;
-}
-
 WebInputEventResult EventHandler::handleWheelEvent(const PlatformWheelEvent& event)
 {
 #if OS(MACOSX)
     // Filter Mac OS specific phases, usually with a zero-delta.
     // https://crbug.com/553732
     // TODO(chongz): EventSender sends events with |PlatformWheelEventPhaseNone|, but it shouldn't.
     const int kPlatformWheelEventPhaseNoEventMask = PlatformWheelEventPhaseEnded | PlatformWheelEventPhaseCancelled | PlatformWheelEventPhaseMayBegin;
     if ((event.phase() & kPlatformWheelEventPhaseNoEventMask) || (event.momentumPhase() & kPlatformWheelEventPhaseNoEventMask))
         return WebInputEventResult::NotHandled;
 #endif
@@ skipping 94 matching lines @@
 WebInputEventResult EventHandler::handleGestureScrollEnd(const PlatformGestureEvent& gestureEvent)
 {
     return m_scrollManager->handleGestureScrollEnd(gestureEvent);
 }
 
 bool EventHandler::isScrollbarHandlingGestures() const
 {
     return m_scrollManager->isScrollbarHandlingGestures();
 }
 
+void EventHandler::setMouseDownMayStartAutoscroll()
+{
+    m_mouseEventManager->setMouseDownMayStartAutoscroll();
+}
+
 bool EventHandler::shouldApplyTouchAdjustment(const PlatformGestureEvent& event) const
 {
     if (m_frame->settings() && !m_frame->settings()->touchAdjustmentEnabled())
         return false;
     return !event.area().isEmpty();
 }
 
 bool EventHandler::bestClickableNodeForHitTestResult(const HitTestResult& result, IntPoint& targetPoint, Node*& targetNode)
 {
     // FIXME: Unify this with the other best* functions which are very similar.
@@ skipping 122 matching lines @@
         enteredFrameChain.append(enteredFrameInDocument);
         Frame* parentFrame = enteredFrameInDocument->tree().parent();
         enteredFrameInDocument = parentFrame && parentFrame->isLocalFrame() ? toLocalFrame(parentFrame) : nullptr;
     }
 
     size_t indexEnteredFrameChain = enteredFrameChain.size();
     LocalFrame* exitedFrameInDocument = m_frame;
     HeapVector<Member<LocalFrame>> exitedFrameChain;
     // Insert the frame from the disagreement between last frames and entered frames
     while (exitedFrameInDocument) {
-        Node* lastNodeUnderTap = exitedFrameInDocument->eventHandler().m_nodeUnderMouse.get();
+        Node* lastNodeUnderTap = exitedFrameInDocument->eventHandler().m_mouseEventManager->getNodeUnderMouse();
         if (!lastNodeUnderTap)
             break;
 
         LocalFrame* nextExitedFrameInDocument = nullptr;
         if (lastNodeUnderTap->isFrameOwnerElement()) {
             HTMLFrameOwnerElement* owner = toHTMLFrameOwnerElement(lastNodeUnderTap);
             if (owner->contentFrame() && owner->contentFrame()->isLocalFrame())
                 nextExitedFrameInDocument = toLocalFrame(owner->contentFrame());
         }
 
@@ skipping 13 matching lines @@
     unsigned modifiers = gestureEvent.getModifiers();
     PlatformMouseEvent fakeMouseMove(gestureEvent.position(), gestureEvent.globalPosition(),
         WebPointerProperties::Button::NoButton, PlatformEvent::MouseMoved, /* clickCount */ 0,
         static_cast<PlatformEvent::Modifiers>(modifiers),
         PlatformMouseEvent::FromTouch, gestureEvent.timestamp(), WebPointerProperties::PointerType::Mouse);
 
     // Update the mouseout/mouseleave event
     size_t indexExitedFrameChain = exitedFrameChain.size();
     while (indexExitedFrameChain) {
         LocalFrame* leaveFrame = exitedFrameChain[--indexExitedFrameChain];
-        leaveFrame->eventHandler().updateMouseEventTargetNodeAndSendEvents(nullptr, fakeMouseMove);
+        leaveFrame->eventHandler().m_mouseEventManager->setNodeUnderMouse(updateMouseEventTargetNode(nullptr), fakeMouseMove);
     }
 
     // update the mouseover/mouseenter event
     while (indexEnteredFrameChain) {
         Frame* parentFrame = enteredFrameChain[--indexEnteredFrameChain]->tree().parent();
         if (parentFrame && parentFrame->isLocalFrame())
-            toLocalFrame(parentFrame)->eventHandler().updateMouseEventTargetNodeAndSendEvents(toHTMLFrameOwnerElement(enteredFrameChain[indexEnteredFrameChain]->owner()), fakeMouseMove);
+            toLocalFrame(parentFrame)->eventHandler().m_mouseEventManager->setNodeUnderMouse(updateMouseEventTargetNode(toHTMLFrameOwnerElement(enteredFrameChain[indexEnteredFrameChain]->owner())), fakeMouseMove);
     }
 }
 
 GestureEventWithHitTestResults EventHandler::targetGestureEvent(const PlatformGestureEvent& gestureEvent, bool readOnly)
 {
     TRACE_EVENT0("input", "EventHandler::targetGestureEvent");
 
     ASSERT(m_frame == m_frame->localFrameRoot());
     // Scrolling events get hit tested per frame (like wheel events do).
     ASSERT(!gestureEvent.isScrollEvent());
@@ skipping 98 matching lines @@
     }
 }
 
 WebInputEventResult EventHandler::sendContextMenuEvent(const PlatformMouseEvent& event, Node* overrideTargetNode)
 {
     FrameView* v = m_frame->view();
     if (!v)
         return WebInputEventResult::NotHandled;
 
     // Clear mouse press state to avoid initiating a drag while context menu is up.
-    m_mousePressed = false;
+    m_mouseEventManager->setMousePressed(false);
     LayoutPoint positionInContents = v->rootFrameToContents(event.position());
     HitTestRequest request(HitTestRequest::Active);
-    MouseEventWithHitTestResults mev = m_frame->document()->prepareMouseEvent(request, positionInContents, event);
-    // Since |Document::prepareMouseEvent()| modifies layout tree for setting
+    MouseEventWithHitTestResults mev = m_frame->document()->performMouseEventHitTest(request, positionInContents, event);
+    // Since |Document::performMouseEventHitTest| modifies layout tree for setting
     // hover element, we need to update layout tree for requirement of
     // |SelectionController::sendContextMenuEvent()|.
     m_frame->document()->updateStyleAndLayoutIgnorePendingStylesheets();
 
     selectionController().sendContextMenuEvent(mev, positionInContents);
 
     Node* targetNode = overrideTargetNode ? overrideTargetNode : mev.innerNode();
-    return dispatchMouseEvent(EventTypeNames::contextmenu, targetNode, 0, event);
+    return m_mouseEventManager->dispatchMouseEvent(updateMouseEventTargetNode(targetNode), EventTypeNames::contextmenu, event, 0);
 }
 
 WebInputEventResult EventHandler::sendContextMenuEventForKey(Element* overrideTargetElement)
 {
     FrameView* view = m_frame->view();
     if (!view)
         return WebInputEventResult::NotHandled;
 
     Document* doc = m_frame->document();
     if (!doc)
@@ skipping 75 matching lines @@
         m_cursorUpdateTimer.startOneShot(cursorUpdateInterval, BLINK_FROM_HERE);
 }
 
 bool EventHandler::cursorUpdatePending()
 {
     return m_cursorUpdateTimer.isActive();
 }
 
 void EventHandler::dispatchFakeMouseMoveEventSoon()
 {
-    if (m_mousePressed)
-        return;
-
-    if (m_mousePositionIsUnknown)
-        return;
-
-    Settings* settings = m_frame->settings();
-    if (settings && !settings->deviceSupportsMouse())
-        return;
-
-    // Reschedule the timer, to prevent dispatching mouse move events
-    // during a scroll. This avoids a potential source of scroll jank.
-    if (m_fakeMouseMoveEventTimer.isActive())
-        m_fakeMouseMoveEventTimer.stop();
-    m_fakeMouseMoveEventTimer.startOneShot(fakeMouseMoveInterval, BLINK_FROM_HERE);
+    m_mouseEventManager->dispatchFakeMouseMoveEventSoon();
 }
 
 void EventHandler::dispatchFakeMouseMoveEventSoonInQuad(const FloatQuad& quad)
 {
-    FrameView* view = m_frame->view();
-    if (!view)
-        return;
-
-    if (!quad.containsPoint(view->rootFrameToContents(m_lastKnownMousePosition)))
-        return;
-
-    dispatchFakeMouseMoveEventSoon();
-}
-
-void EventHandler::fakeMouseMoveEventTimerFired(TimerBase* timer)
-{
-    TRACE_EVENT0("input", "EventHandler::fakeMouseMoveEventTimerFired");
-    ASSERT_UNUSED(timer, timer == &m_fakeMouseMoveEventTimer);
-    ASSERT(!m_mousePressed);
-
-    Settings* settings = m_frame->settings();
-    if (settings && !settings->deviceSupportsMouse())
-        return;
-
-    FrameView* view = m_frame->view();
-    if (!view)
-        return;
-
-    if (!m_frame->page() || !m_frame->page()->focusController().isActive())
-        return;
-
-    // Don't dispatch a synthetic mouse move event if the mouse cursor is not visible to the user.
-    if (!isCursorVisible())
-        return;
-
-    PlatformMouseEvent fakeMouseMoveEvent(m_lastKnownMousePosition, m_lastKnownMouseGlobalPosition, WebPointerProperties::Button::NoButton, PlatformEvent::MouseMoved, 0, static_cast<PlatformEvent::Modifiers>(KeyboardEventManager::getCurrentModifierState()), PlatformMouseEvent::RealOrIndistinguishable, monotonicallyIncreasingTime(), WebPointerProperties::PointerType::Mouse);
-    handleMouseMoveEvent(fakeMouseMoveEvent);
-}
-
-void EventHandler::cancelFakeMouseMoveEvent()
-{
-    m_fakeMouseMoveEventTimer.stop();
-}
-
-bool EventHandler::isCursorVisible() const
-{
-    return m_frame->page()->isCursorVisible();
+    m_mouseEventManager->dispatchFakeMouseMoveEventSoonInQuad(quad);
 }
 
 void EventHandler::setResizingFrameSet(HTMLFrameSetElement* frameSet)
 {
     m_frameSetBeingResized = frameSet;
 }
 
 void EventHandler::resizeScrollableAreaDestroyed()
 {
     m_scrollManager->clearResizeScrollableArea(true);
 }
 
 void EventHandler::hoverTimerFired(TimerBase*)
 {
     TRACE_EVENT0("input", "EventHandler::hoverTimerFired");
     m_hoverTimer.stop();
 
     ASSERT(m_frame);
     ASSERT(m_frame->document());
 
     if (LayoutViewItem layoutItem = m_frame->contentLayoutItem()) {
         if (FrameView* view = m_frame->view()) {
             HitTestRequest request(HitTestRequest::Move);
-            HitTestResult result(request, view->rootFrameToContents(m_lastKnownMousePosition));
+            HitTestResult result(request, view->rootFrameToContents(m_mouseEventManager->lastKnownMousePosition()));
             layoutItem.hitTest(result);
             m_frame->document()->updateHoverActiveState(request, result.innerElement());
         }
     }
 }
 
 void EventHandler::activeIntervalTimerFired(TimerBase*)
 {
     TRACE_EVENT0("input", "EventHandler::activeIntervalTimerFired");
     m_activeIntervalTimer.stop();
@@ skipping 22 matching lines @@
     return m_keyboardEventManager->handleAccessKey(evt);
 }
 
 WebInputEventResult EventHandler::keyEvent(const WebKeyboardEvent& initialKeyEvent)
 {
     return m_keyboardEventManager->keyEvent(initialKeyEvent);
 }
 
 void EventHandler::defaultKeyboardEventHandler(KeyboardEvent* event)
 {
-    m_keyboardEventManager->defaultKeyboardEventHandler(event, m_mousePressNode);
-}
-
-bool EventHandler::dragHysteresisExceeded(const IntPoint& dragLocationInRootFrame) const
-{
-    FrameView* view = m_frame->view();
-    if (!view)
-        return false;
-    IntPoint dragLocation = view->rootFrameToContents(dragLocationInRootFrame);
-    IntSize delta = dragLocation - m_mouseDownPos;
-
-    int threshold = GeneralDragHysteresis;
-    switch (dragState().m_dragType) {
-    case DragSourceActionSelection:
-        threshold = TextDragHysteresis;
-        break;
-    case DragSourceActionImage:
-        threshold = ImageDragHysteresis;
-        break;
-    case DragSourceActionLink:
-        threshold = LinkDragHysteresis;
-        break;
-    case DragSourceActionDHTML:
-        break;
-    case DragSourceActionNone:
-        ASSERT_NOT_REACHED();
-    }
-
-    return abs(delta.width()) >= threshold || abs(delta.height()) >= threshold;
-}
-
-void EventHandler::clearDragDataTransfer()
-{
-    if (dragState().m_dragDataTransfer) {
-        dragState().m_dragDataTransfer->clearDragImage();
-        dragState().m_dragDataTransfer->setAccessPolicy(DataTransferNumb);
-    }
+    m_keyboardEventManager->defaultKeyboardEventHandler(event, m_mouseEventManager->mousePressNode());
 }
 
 void EventHandler::dragSourceEndedAt(const PlatformMouseEvent& event, DragOperation operation)
 {
-    // Send a hit test request so that Layer gets a chance to update the :hover and :active pseudoclasses.
-    HitTestRequest request(HitTestRequest::Release);
-    prepareMouseEvent(request, event);
-
-    if (dragState().m_dragSrc) {
-        dragState().m_dragDataTransfer->setDestinationOperation(operation);
-        // for now we don't care if event handler cancels default behavior, since there is none
-        dispatchDragSrcEvent(EventTypeNames::dragend, event);
-    }
-    clearDragDataTransfer();
-    dragState().m_dragSrc = nullptr;
-    // In case the drag was ended due to an escape key press we need to ensure
-    // that consecutive mousemove events don't reinitiate the drag and drop.
-    m_mouseDownMayStartDrag = false;
+    m_mouseEventManager->dragSourceEndedAt(event, operation);
 }
 
 void EventHandler::updateDragStateAfterEditDragIfNeeded(Element* rootEditableElement)
 {
     // If inserting the dragged contents removed the drag source, we still want to fire dragend at the root editble element.
-    if (dragState().m_dragSrc && !dragState().m_dragSrc->isConnected())
-        dragState().m_dragSrc = rootEditableElement;
-}
-
-// returns if we should continue "default processing", i.e., whether eventhandler canceled
-WebInputEventResult EventHandler::dispatchDragSrcEvent(const AtomicString& eventType, const PlatformMouseEvent& event)
-{
-    return dispatchDragEvent(eventType, dragState().m_dragSrc.get(), event, dragState().m_dragDataTransfer.get());
-}
-
-bool EventHandler::handleDragDropIfPossible(const GestureEventWithHitTestResults& targetedEvent)
-{
-    if (m_frame->settings() && m_frame->settings()->touchDragDropEnabled() && m_frame->view()) {
-        const PlatformGestureEvent& gestureEvent = targetedEvent.event();
-        IntPoint adjustedPoint = gestureEvent.position();
-        unsigned modifiers = gestureEvent.getModifiers();
-
-        // TODO(mustaq): Suppressing long-tap MouseEvents could break
-        // drag-drop. Will do separately because of the risk. crbug.com/606938.
-        PlatformMouseEvent mouseDownEvent(adjustedPoint, gestureEvent.globalPosition(), WebPointerProperties::Button::Left, PlatformEvent::MousePressed, 1,
-            static_cast<PlatformEvent::Modifiers>(modifiers | PlatformEvent::LeftButtonDown),
-            PlatformMouseEvent::FromTouch, WTF::monotonicallyIncreasingTime(), WebPointerProperties::PointerType::Mouse);
-        m_mouseDown = mouseDownEvent;
-
-        PlatformMouseEvent mouseDragEvent(adjustedPoint, gestureEvent.globalPosition(), WebPointerProperties::Button::Left, PlatformEvent::MouseMoved, 1,
-            static_cast<PlatformEvent::Modifiers>(modifiers | PlatformEvent::LeftButtonDown),
-            PlatformMouseEvent::FromTouch, WTF::monotonicallyIncreasingTime(), WebPointerProperties::PointerType::Mouse);
-        HitTestRequest request(HitTestRequest::ReadOnly);
-        MouseEventWithHitTestResults mev = prepareMouseEvent(request, mouseDragEvent);
-        m_mouseDownMayStartDrag = true;
-        dragState().m_dragSrc = nullptr;
-        m_mouseDownPos = m_frame->view()->rootFrameToContents(mouseDragEvent.position());
-        return handleDrag(mev, DragInitiator::Touch);
-    }
-    return false;
-}
-
-bool EventHandler::handleDrag(const MouseEventWithHitTestResults& event, DragInitiator initiator)
-{
-    ASSERT(event.event().type() == PlatformEvent::MouseMoved);
-    // Callers must protect the reference to FrameView, since this function may dispatch DOM
-    // events, causing page/FrameView to go away.
-    ASSERT(m_frame);
-    ASSERT(m_frame->view());
-    if (!m_frame->page())
-        return false;
-
-    if (m_mouseDownMayStartDrag) {
-        HitTestRequest request(HitTestRequest::ReadOnly);
-        HitTestResult result(request, m_mouseDownPos);
-        m_frame->contentLayoutItem().hitTest(result);
-        Node* node = result.innerNode();
-        if (node) {
-            DragController::SelectionDragPolicy selectionDragPolicy = event.event().timestamp() - m_mouseDownTimestamp < TextDragDelay
-                ? DragController::DelayedSelectionDragResolution
-                : DragController::ImmediateSelectionDragResolution;
-            dragState().m_dragSrc = m_frame->page()->dragController().draggableNode(m_frame, node, m_mouseDownPos, selectionDragPolicy, dragState().m_dragType);
-        } else {
-            dragState().m_dragSrc = nullptr;
-        }
-
-        if (!dragState().m_dragSrc)
-            m_mouseDownMayStartDrag = false; // no element is draggable
-    }
-
-    if (!m_mouseDownMayStartDrag)
-        return initiator == DragInitiator::Mouse && !selectionController().mouseDownMayStartSelect() && !m_mouseDownMayStartAutoscroll;
-
-    // We are starting a text/image/url drag, so the cursor should be an arrow
-    // FIXME <rdar://7577595>: Custom cursors aren't supported during drag and drop (default to pointer).
-    m_frame->view()->setCursor(pointerCursor());
-
-    if (initiator == DragInitiator::Mouse && !dragHysteresisExceeded(event.event().position()))
-        return true;
-
-    // Once we're past the hysteresis point, we don't want to treat this gesture as a click
-    invalidateClick();
-
-    if (!tryStartDrag(event)) {
-        // Something failed to start the drag, clean up.
-        clearDragDataTransfer();
-        dragState().m_dragSrc = nullptr;
-    }
-
-    m_mouseDownMayStartDrag = false;
-    // Whether or not the drag actually started, no more default handling (like selection).
-    return true;
-}
-
-bool EventHandler::tryStartDrag(const MouseEventWithHitTestResults& event)
-{
-    // The DataTransfer would only be non-empty if we missed a dragEnd.
-    // Clear it anyway, just to make sure it gets numbified.
-    clearDragDataTransfer();
-
-    dragState().m_dragDataTransfer = createDraggingDataTransfer();
-
-    // Check to see if this a DOM based drag, if it is get the DOM specified drag
-    // image and offset
-    if (dragState().m_dragType == DragSourceActionDHTML) {
-        if (LayoutObject* layoutObject = dragState().m_dragSrc->layoutObject()) {
-            IntRect boundingIncludingDescendants = layoutObject->absoluteBoundingBoxRectIncludingDescendants();
-            IntSize delta = m_mouseDownPos - boundingIncludingDescendants.location();
-            dragState().m_dragDataTransfer->setDragImageElement(dragState().m_dragSrc.get(), IntPoint(delta));
-        } else {
-            // The layoutObject has disappeared, this can happen if the onStartDrag handler has hidden
-            // the element in some way. In this case we just kill the drag.
-            return false;
-        }
-    }
-
-    DragController& dragController = m_frame->page()->dragController();
-    if (!dragController.populateDragDataTransfer(m_frame, dragState(), m_mouseDownPos))
-        return false;
-
-    // If dispatching dragstart brings about another mouse down -- one way
-    // this will happen is if a DevTools user breaks within a dragstart
-    // handler and then clicks on the suspended page -- the drag state is
-    // reset. Hence, need to check if this particular drag operation can
-    // continue even if dispatchEvent() indicates no (direct) cancellation.
-    // Do that by checking if m_dragSrc is still set.
-    m_mouseDownMayStartDrag = dispatchDragSrcEvent(EventTypeNames::dragstart, m_mouseDown) == WebInputEventResult::NotHandled
-        && !m_frame->selection().isInPasswordField() && dragState().m_dragSrc;
-
-    // Invalidate clipboard here against anymore pasteboard writing for security. The drag
-    // image can still be changed as we drag, but not the pasteboard data.
-    dragState().m_dragDataTransfer->setAccessPolicy(DataTransferImageWritable);
-
-    if (m_mouseDownMayStartDrag) {
-        // Dispatching the event could cause Page to go away. Make sure it's still valid before trying to use DragController.
-        if (m_frame->page() && dragController.startDrag(m_frame, dragState(), event.event(), m_mouseDownPos))
-            return true;
-        // Drag was canned at the last minute - we owe m_dragSrc a DRAGEND event
-        dispatchDragSrcEvent(EventTypeNames::dragend, event.event());
-    }
-
-    return false;
+    if (m_mouseEventManager->dragState().m_dragSrc && !m_mouseEventManager->dragState().m_dragSrc->isConnected())
+        m_mouseEventManager->dragState().m_dragSrc = rootEditableElement;
 }
 
 bool EventHandler::handleTextInputEvent(const String& text, Event* underlyingEvent, TextEventInputType inputType)
 {
     // Platforms should differentiate real commands like selectAll from text input in disguise (like insertNewline),
     // and avoid dispatching text input events from keydown default handlers.
     ASSERT(!underlyingEvent || !underlyingEvent->isKeyboardEvent() || toKeyboardEvent(underlyingEvent)->type() == EventTypeNames::keypress);
 
     if (!m_frame)
         return false;
@@ skipping 52 matching lines @@
         m_lastScrollbarUnderMouse = setLast ? scrollbar : nullptr;
     }
 }
 
 WebInputEventResult EventHandler::handleTouchEvent(const PlatformTouchEvent& event)
 {
     TRACE_EVENT0("blink", "EventHandler::handleTouchEvent");
     return m_pointerEventManager->handleTouchEvents(event);
 }
 
-void EventHandler::setLastKnownMousePosition(const PlatformMouseEvent& event)
-{
-    m_mousePositionIsUnknown = false;
-    m_lastKnownMousePosition = event.position();
-    m_lastKnownMouseGlobalPosition = event.globalPosition();
-}
-
 WebInputEventResult EventHandler::passMousePressEventToSubframe(MouseEventWithHitTestResults& mev, LocalFrame* subframe)
 {
     selectionController().passMousePressEventToSubframe(mev);
     WebInputEventResult result = subframe->eventHandler().handleMousePressEvent(mev.event());
     if (result != WebInputEventResult::NotHandled)
         return result;
     return WebInputEventResult::HandledSystem;
 }
 
 WebInputEventResult EventHandler::passMouseMoveEventToSubframe(MouseEventWithHitTestResults& mev, LocalFrame* subframe, HitTestResult* hoveredNode)
 {
-    if (m_mouseDownMayStartDrag)
+    if (m_mouseEventManager->mouseDownMayStartDrag())
         return WebInputEventResult::NotHandled;
     WebInputEventResult result = subframe->eventHandler().handleMouseMoveOrLeaveEvent(mev.event(), hoveredNode);
     if (result != WebInputEventResult::NotHandled)
         return result;
     return WebInputEventResult::HandledSystem;
 }
 
 WebInputEventResult EventHandler::passMouseReleaseEventToSubframe(MouseEventWithHitTestResults& mev, LocalFrame* subframe)
 {
     WebInputEventResult result = subframe->eventHandler().handleMouseReleaseEvent(mev.event());
     if (result != WebInputEventResult::NotHandled)
         return result;
     return WebInputEventResult::HandledSystem;
 }
 
-DataTransfer* EventHandler::createDraggingDataTransfer() const
-{
-    return DataTransfer::create(DataTransfer::DragAndDrop, DataTransferWritable, DataObject::create());
-}
-
-void EventHandler::focusDocumentView()
-{
-    Page* page = m_frame->page();
-    if (!page)
-        return;
-    page->focusController().focusDocumentView(m_frame);
-}
-
 FrameHost* EventHandler::frameHost() const
 {
     if (!m_frame->page())
         return nullptr;
 
     return &m_frame->page()->frameHost();
 }
 
 } // namespace blink