skia: Add support for CHROMIUM_image backed textures.

include/gpu/GrSurface.h

Index: include/gpu/GrSurface.h
diff --git a/include/gpu/GrSurface.h b/include/gpu/GrSurface.h
index 28935009ce8caee78187405c3b50616d7d2e9aed..237d27458dba16a29cad0d699b5e18a2990880d8 100644
--- a/include/gpu/GrSurface.h
+++ b/include/gpu/GrSurface.h
@@ -162,6 +162,7 @@ protected:
 
     void onRelease() override;
     void onAbandon() override;
+    bool reuseable() const override;

[bsalomon, 2016/02/04 16:27:08]

I think this can be done without a new function. If we just don't add a scratch
key when the resource is created it won't be recycled for another purpose.

[erikchen, 2016/02/04 18:44:07]

You're right. Done.

 
 private:
     void invokeReleaseProc() {