Clean-up hit-testing of scrollbars

Source/core/page/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 1414 matching lines @@
     HitTestRequest request(hitType);
     MouseEventWithHitTestResults mev = prepareMouseEvent(request, mouseEvent);
     if (hoveredNode)
         *hoveredNode = mev.hitTestResult();
 
     Scrollbar* scrollbar = 0;
 
     if (m_resizeScrollableArea && m_resizeScrollableArea->inResizeMode())
         m_resizeScrollableArea->resize(mouseEvent, m_offsetFromResizeCorner);
     else {
-        if (FrameView* view = m_frame->view())
-            scrollbar = view->scrollbarAtPoint(mouseEvent.position());
-
         if (!scrollbar)
             scrollbar = mev.scrollbar();
 
         updateLastScrollbarUnderMouse(scrollbar, !m_mousePressed);
         if (onlyUpdateScrollbars)
             return true;
     }
 
     bool swallowEvent = false;
     RefPtr<LocalFrame> newSubframe = m_capturingMouseEventsNode.get() ? subframeForTargetNode(m_capturingMouseEventsNode.get()) : subframeForHitTestResult(mev);
@@ skipping 421 matching lines @@
 {
     updateMouseEventTargetNode(targetNode, mouseEvent, setUnder);
     return !m_nodeUnderMouse || m_nodeUnderMouse->dispatchMouseEvent(mouseEvent, eventType, clickCount);
 }
 
 // The return value means 'swallow event' (was handled), as for other handle* functions.
 bool EventHandler::handleMouseFocus(const PlatformMouseEvent& mouseEvent)
 {
     // If clicking on a frame scrollbar, do not mess up with content focus.
     if (FrameView* view = m_frame->view()) {
-        if (view->scrollbarAtPoint(mouseEvent.position()))
+        if (view->scrollbarAtWindowPoint(mouseEvent.position()))
             return false;
     }
 
     // The layout needs to be up to date to determine if an element is focusable.
     m_frame->document()->updateLayoutIgnorePendingStylesheets();
 
     Element* element = 0;
     if (m_nodeUnderMouse)
         element = m_nodeUnderMouse->isElementNode() ? toElement(m_nodeUnderMouse) : m_nodeUnderMouse->parentOrShadowHostElement();
     for (; element; element = element->parentOrShadowHostElement()) {
@@ skipping 261 matching lines @@
         HitTestResult result(viewPoint);
         document->renderView()->hitTest(request, result);
 
         eventTarget = result.innerNode();
 
         m_lastGestureScrollOverWidget = result.isOverWidget();
         m_scrollGestureHandlingNode = eventTarget;
         m_previousGestureScrolledNode = nullptr;
 
         if (!scrollbar)
-            scrollbar = view->scrollbarAtPoint(gestureEvent.position());
-        if (!scrollbar)
             scrollbar = result.scrollbar();
     }
 
     if (scrollbar) {
         bool eventSwallowed = scrollbar->gestureEvent(gestureEvent);
         if (gestureEvent.type() == PlatformEvent::GestureScrollEnd
             || gestureEvent.type() == PlatformEvent::GestureFlingStart
             || !eventSwallowed) {
             m_scrollbarHandlingScrollGesture = nullptr;
         }
@@ skipping 25 matching lines @@
     default:
         ASSERT_NOT_REACHED();
         return false;
     }
 }
 
 bool EventHandler::handleGestureTap(const GestureEventWithHitTestResults& targetedEvent)
 {
     RefPtr<FrameView> protector(m_frame->view());
     const PlatformGestureEvent& gestureEvent = targetedEvent.event();
+    HitTestRequest::HitTestRequestType hitType = getHitTypeForGestureType(gestureEvent.type());
 
     UserGestureIndicator gestureIndicator(DefinitelyProcessingUserGesture);
 
     unsigned modifierFlags = 0;
     if (gestureEvent.altKey())
         modifierFlags |= PlatformEvent::AltKey;
     if (gestureEvent.ctrlKey())
         modifierFlags |= PlatformEvent::CtrlKey;
     if (gestureEvent.metaKey())
         modifierFlags |= PlatformEvent::MetaKey;
@@ skipping 11 matching lines @@
         NoButton, PlatformEvent::MouseMoved, /* clickCount */ 0,
         modifiers, PlatformMouseEvent::FromTouch, gestureEvent.timestamp());
     dispatchMouseEvent(EventTypeNames::mousemove, currentHitTest.innerNode(), 0, fakeMouseMove, true);
 
     // Do a new hit-test in case the mousemove event changed the DOM.
     // Note that if the original hit test wasn't over an element (eg. was over a scrollbar) we
     // don't want to re-hit-test because it may be in the wrong frame (and there's no way the page
     // could have seen the event anyway).
     // FIXME: Use a hit-test cache to avoid unnecessary hit tests. http://crbug.com/398920
     if (currentHitTest.innerNode())
-        currentHitTest = hitTestResultInFrame(m_frame, adjustedPoint, HitTestRequest::ReadOnly);
+        currentHitTest = hitTestResultInFrame(m_frame, adjustedPoint, hitType);
     m_clickNode = currentHitTest.innerNode();
     if (m_clickNode && m_clickNode->isTextNode())
         m_clickNode = NodeRenderingTraversal::parent(m_clickNode.get());
 
     PlatformMouseEvent fakeMouseDown(adjustedPoint, gestureEvent.globalPosition(),
         LeftButton, PlatformEvent::MousePressed, gestureEvent.tapCount(),
         modifiers, PlatformMouseEvent::FromTouch,  gestureEvent.timestamp());
     bool swallowMouseDownEvent = !dispatchMouseEvent(EventTypeNames::mousedown, currentHitTest.innerNode(), gestureEvent.tapCount(), fakeMouseDown, true);
     if (!swallowMouseDownEvent)
         swallowMouseDownEvent = handleMouseFocus(fakeMouseDown);
     if (!swallowMouseDownEvent)
         swallowMouseDownEvent = handleMousePressEvent(MouseEventWithHitTestResults(fakeMouseDown, currentHitTest));
 
     // FIXME: Use a hit-test cache to avoid unnecessary hit tests. http://crbug.com/398920
     if (currentHitTest.innerNode())
-        currentHitTest = hitTestResultInFrame(m_frame, adjustedPoint, HitTestRequest::ReadOnly);
+        currentHitTest = hitTestResultInFrame(m_frame, adjustedPoint, hitType);
     PlatformMouseEvent fakeMouseUp(adjustedPoint, gestureEvent.globalPosition(),
         LeftButton, PlatformEvent::MouseReleased, gestureEvent.tapCount(),
         modifiers, PlatformMouseEvent::FromTouch,  gestureEvent.timestamp());
     bool swallowMouseUpEvent = !dispatchMouseEvent(EventTypeNames::mouseup, currentHitTest.innerNode(), gestureEvent.tapCount(), fakeMouseUp, false);
 
     bool swallowClickEvent = false;
     if (m_clickNode) {
         if (currentHitTest.innerNode()) {
             Node* clickTargetNode = currentHitTest.innerNode()->commonAncestor(*m_clickNode, parentForClickEvent);
             swallowClickEvent = !dispatchMouseEvent(EventTypeNames::click, clickTargetNode, gestureEvent.tapCount(), fakeMouseUp, true);
@@ skipping 311 matching lines @@
     // we don't yet apply hover/active state here because we need to resolve touch adjustment
     // first so that we apply hover/active it to the final adjusted node.
     IntPoint hitTestPoint = m_frame->view()->windowToContents(gestureEvent.position());
     LayoutSize padding;
     if (shouldApplyTouchAdjustment(gestureEvent)) {
         padding = gestureEvent.area();
         padding.scale(1.f / 2);
     }
     HitTestResult hitTestResult = hitTestResultAtPoint(hitTestPoint, hitType | HitTestRequest::ReadOnly, padding);
 
-    // Hit-test the main frame scrollbars (in addition to the child-frame and RenderLayer
-    // scroll bars checked by the hit-test code.
-    if (!hitTestResult.scrollbar()) {
-        if (FrameView* view = m_frame->view()) {
-            hitTestResult.setScrollbar(view->scrollbarAtPoint(gestureEvent.position()));
-        }
-    }
-
     // Adjust the location of the gesture to the most likely nearby node, as appropriate for the
     // type of event.
     PlatformGestureEvent adjustedEvent = gestureEvent;
     applyTouchAdjustment(&adjustedEvent, &hitTestResult);
 
     // Do a new hit-test at the (adjusted) gesture co-ordinates. This is necessary because
     // rect-based hit testing and touch adjustment sometimes return a different node than
     // what a point-based hit test would return for the same point.
     // FIXME: Fix touch adjustment to avoid the need for a redundant hit test. http://crbug.com/398914
     if (shouldApplyTouchAdjustment(gestureEvent)) {
         LocalFrame* hitFrame = hitTestResult.innerNodeFrame();
         if (!hitFrame)
             hitFrame = m_frame;
         hitTestResult = hitTestResultInFrame(hitFrame, hitFrame->view()->windowToContents(adjustedEvent.position()), hitType | HitTestRequest::ReadOnly);
-        // FIXME: HitTest entry points should really check for main frame scrollbars themselves.
-        if (!hitTestResult.scrollbar()) {
-            if (FrameView* view = m_frame->view()) {
-                hitTestResult.setScrollbar(view->scrollbarAtPoint(gestureEvent.position()));
-            }
-        }
     }
 
     // If we did a rect-based hit test it must be resolved to the best single node by now to
     // ensure consumers don't accidentally use one of the other candidates.
     ASSERT(!hitTestResult.isRectBasedTest());
 
     // Now apply hover/active state to the final target.
     // FIXME: This is supposed to send mouseenter/mouseleave events, but doesn't because we
     // aren't passing a PlatformMouseEvent.
     HitTestRequest request(hitType | HitTestRequest::AllowChildFrameContent);
     if (!request.readOnly())
         m_frame->document()->updateHoverActiveState(request, hitTestResult.innerElement());
 
     if (shouldKeepActiveForMinInterval) {
         m_lastDeferredTapElement = hitTestResult.innerElement();
         m_activeIntervalTimer.startOneShot(minimumActiveInterval - activeInterval, FROM_HERE);
     }
 
     return GestureEventWithHitTestResults(adjustedEvent, hitTestResult);
 }
 
 HitTestRequest::HitTestRequestType EventHandler::getHitTypeForGestureType(PlatformEvent::Type type)
 {
-    HitTestRequest::HitTestRequestType hitType = HitTestRequest::TouchEvent | HitTestRequest::AllowFrameScrollbars;
+    HitTestRequest::HitTestRequestType hitType = HitTestRequest::TouchEvent;
     switch (type) {
     case PlatformEvent::GestureShowPress:
     case PlatformEvent::GestureTapUnconfirmed:
         return hitType | HitTestRequest::Active;
     case PlatformEvent::GestureTapDownCancel:
         // A TapDownCancel received when no element is active shouldn't really be changing hover state.
         if (!m_frame->document()->activeHoverElement())
             hitType |= HitTestRequest::ReadOnly;
         return hitType | HitTestRequest::Release;
     case PlatformEvent::GestureTap:
@@ skipping 803 matching lines @@
 }
 
 void EventHandler::setFrameWasScrolledByUser()
 {
     if (FrameView* view = m_frame->view())
         view->setWasScrolledByUser(true);
 }
 
 bool EventHandler::passMousePressEventToScrollbar(MouseEventWithHitTestResults& mev)
 {
-    // First try to use the frame scrollbar.
-    FrameView* view = m_frame->view();
-    Scrollbar* scrollbar = view ? view->scrollbarAtPoint(mev.event().position()) : 0;
-
-    // Then try the scrollbar in the hit test.
-    if (!scrollbar)
-        scrollbar = mev.scrollbar();
-
+    Scrollbar* scrollbar = mev.scrollbar();
     updateLastScrollbarUnderMouse(scrollbar, true);
 
     if (!scrollbar || !scrollbar->enabled())
         return false;
     setFrameWasScrolledByUser();
     scrollbar->mouseDown(mev.event());
     return true;
 }
 
 // If scrollbar (under mouse) is different from last, send a mouse exited. Set
@@ skipping 32 matching lines @@
     }
 }
 
 HitTestResult EventHandler::hitTestResultInFrame(LocalFrame* frame, const LayoutPoint& point, HitTestRequest::HitTestRequestType hitType)
 {
     HitTestResult result(point);
 
     if (!frame || !frame->contentRenderer())
         return result;
     if (frame->view()) {
-        IntRect rect = frame->view()->visibleContentRect();
+        IntRect rect = frame->view()->visibleContentRect(IncludeScrollbars);
         if (!rect.contains(roundedIntPoint(point)))
             return result;
     }
     frame->contentRenderer()->hitTest(HitTestRequest(hitType), result);
     return result;
 }
 
 bool EventHandler::handleTouchEvent(const PlatformTouchEvent& event)
 {
     TRACE_EVENT0("blink", "EventHandler::handleTouchEvent");
@@ skipping 352 matching lines @@
 unsigned EventHandler::accessKeyModifiers()
 {
 #if OS(MACOSX)
     return PlatformEvent::CtrlKey | PlatformEvent::AltKey;
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 } // namespace blink