Chromium compositor change implementing page-scale driven pinch-zoom.

cc/LayerChromium.h

Index: cc/LayerChromium.h
===================================================================
--- cc/LayerChromium.h	(revision 159486)
+++ cc/LayerChromium.h	(working copy)
@@ -156,7 +156,8 @@
 
     IntSize scrollDelta() const { return IntSize(); }
 
-    float pageScaleDelta() const { return 1; }
+    void setImplTransform(const WebKit::WebTransformationMatrix&);
+    const WebKit::WebTransformationMatrix& implTransform() const { return m_implTransform; }
 
     void setDoubleSided(bool);
     bool doubleSided() const { return m_doubleSided; }
@@ -375,6 +376,8 @@
     float m_contentsScale;
     bool m_boundsContainPageScale;
 
+    WebKit::WebTransformationMatrix m_implTransform;
+
     WebKit::WebAnimationDelegate* m_layerAnimationDelegate;
     WebKit::WebLayerScrollClient* m_layerScrollClient;
 };