Reduce compositing update in Silk's toggle_drawer by 20%

Source/core/rendering/compositing/CompositedLayerMapping.h

 /*
  * Copyright (C) 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
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  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 #ifndef CompositedLayerMapping_h
 #define CompositedLayerMapping_h
 
 #include "core/rendering/RenderLayer.h"
+#include "core/rendering/compositing/GraphicsLayerUpdater.h"
 #include "platform/geometry/FloatPoint.h"
 #include "platform/geometry/FloatPoint3D.h"
 #include "platform/graphics/GraphicsLayer.h"
 #include "platform/graphics/GraphicsLayerClient.h"
 #include "platform/transforms/TransformationMatrix.h"
 
 namespace WebCore {
 
 class KeyframeList;
 class RenderLayerCompositor;
@@ skipping 47 matching lines @@
         CompositingChildrenOnly = 1 << 0,
         NeedsFullRepaint = 1 << 1,
         IsUpdateRoot = 1 << 2
     };
     typedef unsigned UpdateAfterLayoutFlags;
     void updateAfterLayout(UpdateAfterLayoutFlags);
 
     // Returns true if layer configuration changed.
     bool updateGraphicsLayerConfiguration();
     // Update graphics layer position and bounds.
-    void updateGraphicsLayerGeometry(); // make private
+    GraphicsLayerUpdater::UpdateType updateGraphicsLayerGeometry(GraphicsLayerUpdater::UpdateType);
     // Update whether layer needs blending.
     void updateContentsOpaque();
 
     GraphicsLayer* mainGraphicsLayer() const { return m_graphicsLayer.get(); }
 
     // Layer to clip children
     bool hasClippingLayer() const { return m_childContainmentLayer; }
     GraphicsLayer* clippingLayer() const { return m_childContainmentLayer.get(); }
 
     // Layer to get clipped by ancestor
@@ skipping 80 matching lines @@
 
     GraphicsLayer* layerForHorizontalScrollbar() const { return m_layerForHorizontalScrollbar.get(); }
     GraphicsLayer* layerForVerticalScrollbar() const { return m_layerForVerticalScrollbar.get(); }
     GraphicsLayer* layerForScrollCorner() const { return m_layerForScrollCorner.get(); }
 
     void updateFilters(const RenderStyle*);
     bool canCompositeFilters() const { return m_canCompositeFilters; }
 
     void setBlendMode(blink::WebBlendMode);
 
+    void setNeedsGeometryUpdate();
+    void clearNeedsGeometryUpdate();
+
     virtual String debugName(const GraphicsLayer*) OVERRIDE;
 
     LayoutSize subpixelAccumulation() const { return m_subpixelAccumulation; }
 private:
     void createPrimaryGraphicsLayer();
     void destroyGraphicsLayers();
 
     PassOwnPtr<GraphicsLayer> createGraphicsLayer(CompositingReasons);
     bool toggleScrollbarLayerIfNeeded(OwnPtr<GraphicsLayer>&, bool needsLayer, CompositingReasons);
 
@@ skipping 138 matching lines @@
     OwnPtr<GraphicsLayer> m_layerForVerticalScrollbar;
     OwnPtr<GraphicsLayer> m_layerForScrollCorner;
 
     OwnPtr<GraphicsLayer> m_squashingContainmentLayer; // Only used if any squashed layers exist, to contain the squashed layers as siblings to the rest of the GraphicsLayer tree chunk.
     OwnPtr<GraphicsLayer> m_squashingLayer; // Only used if any squashed layers exist, this is the backing that squashed layers paint into.
     Vector<GraphicsLayerPaintInfo> m_squashedLayers;
 
     LayoutRect m_compositedBounds;
     LayoutSize m_subpixelAccumulation; // The accumulated subpixel offset of the compositedBounds compared to absolute coordinates.
 
-    bool m_artificiallyInflatedBounds; // bounds had to be made non-zero to make transform-origin work
-    bool m_isMainFrameRenderViewLayer;
-    bool m_requiresOwnBackingStoreForIntrinsicReasons;
-    bool m_requiresOwnBackingStoreForAncestorReasons;
-    bool m_canCompositeFilters;
-    bool m_backgroundLayerPaintsFixedRootBackground;
+    bool m_artificiallyInflatedBounds : 1; // bounds had to be made non-zero to make transform-origin work
+    bool m_isMainFrameRenderViewLayer : 1;
+    bool m_requiresOwnBackingStoreForIntrinsicReasons : 1;
+    bool m_requiresOwnBackingStoreForAncestorReasons : 1;
+    bool m_canCompositeFilters : 1;
+    bool m_backgroundLayerPaintsFixedRootBackground : 1;
+    bool m_needToUpdateGeometry : 1;
+    bool m_needToUpdateGeometryOfAllDecendants : 1;
 };
 
 } // namespace WebCore
 
 #endif // CompositedLayerMapping_h