Merge 92520 - [chromium] Accelerated canvas breaks when moving canvases or resources between Pages

Source/WebCore/platform/graphics/chromium/CanvasLayerChromium.h

Index: Source/WebCore/platform/graphics/chromium/CanvasLayerChromium.h
===================================================================
--- Source/WebCore/platform/graphics/chromium/CanvasLayerChromium.h	(revision 93254)
+++ Source/WebCore/platform/graphics/chromium/CanvasLayerChromium.h	(working copy)
@@ -50,10 +50,9 @@
 protected:
     explicit CanvasLayerChromium(GraphicsLayerChromium* owner);
 
+    virtual unsigned textureId() const = 0;
     virtual const char* layerTypeAsString() const { return "CanvasLayer"; }
 
-    bool m_textureChanged;
-    unsigned m_textureId;
     bool m_hasAlpha;
     bool m_premultipliedAlpha;
 };