Extract more of the mouse logic from EventHandler

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

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/input/EventHandlingUtil.h"
 
 #include "core/frame/FrameView.h"
+#include "core/frame/LocalFrame.h"
 #include "core/layout/api/LayoutViewItem.h"
+#include "core/paint/PaintLayer.h"
+#include "platform/scroll/ScrollableArea.h"
 
 namespace blink {
 namespace EventHandlingUtil {
 
 HitTestResult hitTestResultInFrame(LocalFrame* frame,
                                    const LayoutPoint& point,
                                    HitTestRequest::HitTestRequestType hitType) {
   HitTestResult result(HitTestRequest(hitType), point);
 
   if (!frame || frame->contentLayoutItem().isNull())
@@ skipping 37 matching lines @@
     case DispatchEventResult::CanceledByDefaultEventHandler:
       return WebInputEventResult::HandledSystem;
     case DispatchEventResult::CanceledBeforeDispatch:
       return WebInputEventResult::HandledSuppressed;
     default:
       NOTREACHED();
       return WebInputEventResult::HandledSystem;
   }
 }
 
+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* associatedScrollableArea(const PaintLayer* layer) {
+  if (PaintLayerScrollableArea* scrollableArea = layer->getScrollableArea()) {
+    if (scrollableArea->scrollsOverflow())
+      return scrollableArea;
+  }
+
+  return nullptr;
+}
+
+ContainerNode* 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);
+}
+
+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;
+}
+
+MouseEventWithHitTestResults performMouseEventHitTest(
+    LocalFrame* frame,
+    const HitTestRequest& request,
+    const PlatformMouseEvent& mev) {
+  DCHECK(frame);
+  DCHECK(frame->document());
+
+  return frame->document()->performMouseEventHitTest(
+      request, contentPointFromRootFrame(frame, mev.position()), mev);
+}
+
 }  // namespace EventHandlingUtil
 }  // namespace blink