REGRESSION (r183300): Fixed elements flash when scrolling

[WebKit-https.git] / Source / WebCore / platform / graphics / GraphicsLayer.h

diff --git a/Source/WebCore/platform/graphics/GraphicsLayer.h b/Source/WebCore/platform/graphics/GraphicsLayer.h
index 275d3f0fea9c0e1b9dbbe1a58f519b41b3501bd1..9fa72513b236bad59a06d8e3082bf8243a15751a 100644 (file)
--- a/Source/WebCore/platform/graphics/GraphicsLayer.h
+++ b/Source/WebCore/platform/graphics/GraphicsLayer.h
@@ -490,6 +490,10 @@ public:
 
     float pageScaleFactor() const { return m_client.pageScaleFactor(); }
     float deviceScaleFactor() const { return m_client.deviceScaleFactor(); }
+    
+    // Whether this layer (and descendants) can detach backing store when outside the coverage area.
+    virtual void setAllowsBackingStoreDetachment(bool) { }
+    virtual bool allowsBackingStoreDetachment() const { return true; }
 
     virtual void deviceOrPageScaleFactorChanged() { }
     WEBCORE_EXPORT void noteDeviceOrPageScaleFactorChangedIncludingDescendants();