Rework compositor touch hit testing

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 7201 matching lines @@
                     pos = FloatPoint(additionalOffset.x() + box->x(), additionalOffset.y() + box->y());
                 box->addFocusRingRects(rects, flooredLayoutPoint(pos), paintContainer);
             }
         }
     }
 
     if (inlineElementContinuation())
         inlineElementContinuation()->addFocusRingRects(rects, flooredLayoutPoint(additionalOffset + inlineElementContinuation()->containingBlock()->location() - location()), paintContainer);
 }
 
+void RenderBlock::computeOwnHitTestRects(Vector<IntRect>& rects, const LayoutPoint& layerOffset) const
+{
+    RenderBox::computeOwnHitTestRects(rects, layerOffset);
+
+    if (hasHorizontalLayoutOverflow() || hasVerticalLayoutOverflow()) {
+        for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
+            LayoutUnit top = max<LayoutUnit>(curr->lineTop(), curr->top());
+            LayoutUnit bottom = min<LayoutUnit>(curr->lineBottom(), curr->top() + curr->height());
+            IntRect rect(pixelSnappedIntRect(layerOffset.x() + curr->x(), layerOffset.y() + top, curr->width(), bottom - top));
+            // It's common for this rect to be entirely contained in our box, so exclude that simple case.
+            if (!rect.isEmpty() && (rects.isEmpty() || !rects[0].contains(rect)))
+                rects.append(rect);
+        }
+    }
+}
+
 RenderBox* RenderBlock::createAnonymousBoxWithSameTypeAs(const RenderObject* parent) const
 {
     if (isAnonymousColumnsBlock())
         return createAnonymousColumnsWithParentRenderer(parent);
     if (isAnonymousColumnSpanBlock())
         return createAnonymousColumnSpanWithParentRenderer(parent);
     return createAnonymousWithParentRendererAndDisplay(parent, style()->display());
 }
 
 bool RenderBlock::hasNextPage(LayoutUnit logicalOffset, PageBoundaryRule pageBoundaryRule) const
@@ skipping 916 matching lines @@
 {
     memoryInstrumentation->addRootObject(gColumnInfoMap, WebCoreMemoryTypes::RenderingStructures);
     memoryInstrumentation->addRootObject(gPositionedDescendantsMap, WebCoreMemoryTypes::RenderingStructures);
     memoryInstrumentation->addRootObject(gPercentHeightDescendantsMap, WebCoreMemoryTypes::RenderingStructures);
     memoryInstrumentation->addRootObject(gPositionedContainerMap, WebCoreMemoryTypes::RenderingStructures);
     memoryInstrumentation->addRootObject(gPercentHeightContainerMap, WebCoreMemoryTypes::RenderingStructures);
     memoryInstrumentation->addRootObject(gDelayedUpdateScrollInfoSet, WebCoreMemoryTypes::RenderingStructures);
 }
 
 } // namespace WebCore