Move visual rect unioning between paired items to cc::DisplayItemList.

third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.cpp

Index: third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.cpp b/third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.cpp
index c3f23f10a33fa5d6f954b9215cd12441797ab435..c7ecf68b4cf1047b58b55e0c380c628430fdcc0c 100644
--- a/third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.cpp
+++ b/third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.cpp
@@ -34,36 +34,7 @@ DisplayItem& DisplayItemList::appendByMoving(DisplayItem& item)
 
 void DisplayItemList::appendVisualRect(const IntRect& visualRect)
 {
-    size_t itemIndex = m_visualRects.size();
-    const DisplayItem& item = (*this)[itemIndex];
-
-    // For paired display items such as transforms, since we are not guaranteed containment, the
-    // visual rect must comprise the union of the visual rects for all items within its block.
-
-    if (item.isBegin()) {
-        m_visualRects.append(visualRect);
-        m_beginItemIndices.append(itemIndex);
-
-    } else if (item.isEnd()) {
-        size_t lastBeginIndex = m_beginItemIndices.last();
-        m_beginItemIndices.removeLast();
-
-        // Ending bounds match the starting bounds.
-        m_visualRects.append(m_visualRects[lastBeginIndex]);
-
-        // The block that ended needs to be included in the bounds of the enclosing block.
-        growCurrentBeginItemVisualRect(m_visualRects[lastBeginIndex]);
-
-    } else {
-        m_visualRects.append(visualRect);
-        growCurrentBeginItemVisualRect(visualRect);
-    }
-}
-
-void DisplayItemList::growCurrentBeginItemVisualRect(const IntRect& visualRect)
-{
-    if (!m_beginItemIndices.isEmpty())
-        m_visualRects[m_beginItemIndices.last()].unite(visualRect);
+    m_visualRects.append(visualRect);
 }
 
 DisplayItemList::Range<DisplayItemList::iterator>