Implement GL support for buffer textures

include/gpu/GrTexture.h

Index: include/gpu/GrTexture.h
diff --git a/include/gpu/GrTexture.h b/include/gpu/GrTexture.h
index 1d589eddcef3ba44504cda3e1785a263cbda6996..6571ba85c3cb411c59a3f7f69c95414d282875fb 100644
--- a/include/gpu/GrTexture.h
+++ b/include/gpu/GrTexture.h
@@ -23,6 +23,12 @@ public:
     GrSLType samplerType() const { return fSamplerType; }
 
     /**
+     * Returns true if the classic texturing options found in GrTextureParams are applicable for
+     * this texture. These may not apply for nonstandard types of textures (e.g. buffer texture).
+     */
+    bool supportsTextureParams() const { return kSamplerBuffer_GrSLType != fSamplerType; }
+
+    /**
      *  Return the native ID or handle to the texture, depending on the
      *  platform. e.g. on OpenGL, return the texture ID.
      */