Moving HitTest function to DeprecatedPaintLayerStackingNode.

Source/core/paint/DeprecatedPaintLayerStackingNode.h

Index: Source/core/paint/DeprecatedPaintLayerStackingNode.h
diff --git a/Source/core/paint/DeprecatedPaintLayerStackingNode.h b/Source/core/paint/DeprecatedPaintLayerStackingNode.h
index 4fd6b7c55c2d562b3b7cb43cebb12a9a69502fc5..cbdc060ac956cc2aa14f231f1ce6426d632d1e79 100644
--- a/Source/core/paint/DeprecatedPaintLayerStackingNode.h
+++ b/Source/core/paint/DeprecatedPaintLayerStackingNode.h
@@ -97,6 +97,10 @@ public:
     void setLayerListMutationAllowed(bool flag) { m_layerListMutationAllowed = flag; }
 #endif
 
+    // The hitTest() method looks for mouse events by walking layers that intersect the point from front to back.

[Julien - ping for review, 2015/06/05 00:46:55]

This ancient comment could definitely be improved upon.

Chad, describing in more details what you've learned about hit testing here
would be super helpful. Especially since this is the actual starting point of
hit testing.

[chadarmstrong, 2015/06/05 17:24:35]

I was planning on it, but I would rather hold off until all the changes are
done.

+    bool hitTest(HitTestResult&);
+    bool hitTest(const HitTestRequest&, const HitTestLocation&, HitTestResult&);
+
 private:
     friend class DeprecatedPaintLayerStackingNodeIterator;
     friend class DeprecatedPaintLayerStackingNodeReverseIterator;