Extract more of the mouse logic from EventHandler

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

Index: third_party/WebKit/Source/core/input/EventHandlingUtil.cpp
diff --git a/third_party/WebKit/Source/core/input/EventHandlingUtil.cpp b/third_party/WebKit/Source/core/input/EventHandlingUtil.cpp
index 2a3fcca5797449ef880fa23c24d7a9b3043de31c..908de11084e01bf8a44b9de6c32cb8ae855d5339 100644
--- a/third_party/WebKit/Source/core/input/EventHandlingUtil.cpp
+++ b/third_party/WebKit/Source/core/input/EventHandlingUtil.cpp
@@ -5,7 +5,10 @@
 #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 {
@@ -63,5 +66,57 @@ WebInputEventResult toWebInputEventResult(DispatchEventResult result) {
   }
 }
 
+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