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

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

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/graphics/paint/DisplayItemList.h"
 
 #include "platform/graphics/paint/DrawingDisplayItem.h"
 #include "platform/graphics/paint/PaintChunk.h"
 #include "third_party/skia/include/core/SkPictureAnalyzer.h"
 
@@ skipping 16 matching lines @@
     ASSERT(!item.hasValidClient());
 #ifndef NDEBUG
     // Save original debug string in the old item to help debugging.
     item.setClientDebugString(originalDebugString);
 #endif
     return result;
 }
 
 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>
 DisplayItemList::itemsInPaintChunk(const PaintChunk& paintChunk)
 {
     return Range<iterator>(begin() + paintChunk.beginIndex, begin() + paintChunk.endIndex);
 }
 
 DisplayItemList::Range<DisplayItemList::const_iterator>
 DisplayItemList::itemsInPaintChunk(const PaintChunk& paintChunk) const
 {
     return Range<const_iterator>(begin() + paintChunk.beginIndex, begin() + paintChunk.endIndex);
 }
 
 } // namespace blink