Determine WebGL back-buffer on Mali-400 GPU

Source/platform/graphics/gpu/DrawingBuffer.h

Index: Source/platform/graphics/gpu/DrawingBuffer.h
diff --git a/Source/platform/graphics/gpu/DrawingBuffer.h b/Source/platform/graphics/gpu/DrawingBuffer.h
index 81c98223027a66456c277fb06c4bb9284ae22c54..70bea84f65e075e9b8ffada424f44dd035b083ab 100644
--- a/Source/platform/graphics/gpu/DrawingBuffer.h
+++ b/Source/platform/graphics/gpu/DrawingBuffer.h
@@ -33,6 +33,7 @@
 
 #include "platform/PlatformExport.h"
 #include "platform/geometry/IntSize.h"
+#include "platform/gpu/GPUBlackList.h"
 #include "platform/graphics/GraphicsTypes3D.h"
 #include "platform/graphics/gpu/WebGLImageConversion.h"
 #include "public/platform/WebExternalTextureLayerClient.h"
@@ -164,6 +165,7 @@ public:
 
     int sampleCount() const { return m_sampleCount; }
     bool explicitResolveOfMultisampleData() const { return m_multisampleMode == ExplicitResolve; };
+    bool isRGBTextureSupported() const { return m_RGBTextureSupported; }
 
 protected: // For unittests
     DrawingBuffer(
@@ -222,6 +224,9 @@ private:
     void allocateTextureMemory(TextureInfo*, const IntSize&);
     void deleteChromiumImageForTexture(TextureInfo*);
 
+    GPUBlackList gpuBlackList() { return m_gpuBlackList; }
+    void determineRGBTextureSupport();
+
     PreserveDrawingBuffer m_preserveDrawingBuffer;
     bool m_scissorEnabled;
     Platform3DObject m_texture2DBinding;
@@ -280,6 +285,7 @@ private:
     bool m_destructionInProgress;
     bool m_isHidden;
     SkFilterQuality m_filterQuality;
+    bool m_RGBTextureSupported;
 
     OwnPtr<WebExternalTextureLayer> m_layer;
 
@@ -297,6 +303,8 @@ private:
 
     // Used to flip a bitmap vertically.
     Vector<uint8_t> m_scanline;
+
+    GPUBlackList m_gpuBlackList;
 };
 
 } // namespace blink