Fix RenderBlock::nodeAtPoint() for scrollbars of hidden and pointer-events:none elements

Source/core/rendering/RenderBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 3061 matching lines @@
 
     if (!isRenderView()) {
         // Check if we need to do anything at all.
         LayoutRect overflowBox = visualOverflowRect();
         flipForWritingMode(overflowBox);
         overflowBox.moveBy(adjustedLocation);
         if (!locationInContainer.intersects(overflowBox))
             return false;
     }
 
-    if ((hitTestAction == HitTestBlockBackground || hitTestAction == HitTestChildBlockBackground) && isPointInOverflowControl(result, locationInContainer.point(), adjustedLocation)) {
+    if ((hitTestAction == HitTestBlockBackground || hitTestAction == HitTestChildBlockBackground)
+        && visibleToHitTestRequest(request)
+        && isPointInOverflowControl(result, locationInContainer.point(), adjustedLocation)) {
         updateHitTestResult(result, locationInContainer.point() - localOffset);
         // FIXME: isPointInOverflowControl() doesn't handle rect-based tests yet.
         if (!result.addNodeToRectBasedTestResult(nodeForHitTest(), request, locationInContainer))
            return true;
     }
 
     // If we have clipping, then we can't have any spillout.
     bool useOverflowClip = hasOverflowClip() && !hasSelfPaintingLayer();
     bool useClip = (hasControlClip() || useOverflowClip);
     bool checkChildren = !useClip || (hasControlClip() ? locationInContainer.intersects(controlClipRect(adjustedLocation)) : locationInContainer.intersects(overflowClipRect(adjustedLocation, locationInContainer.region(), IncludeOverlayScrollbarSize)));
@@ skipping 2759 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace WebCore