cc: Adding support for RGBA_4444 tile textures

cc/resources/resource_provider.h

Index: cc/resources/resource_provider.h
diff --git a/cc/resources/resource_provider.h b/cc/resources/resource_provider.h
index b5dccc8f046a71c6a2a33906d745d37727b05ca6..0361503a9ca7201c639253e17b0dee540eda063d 100644
--- a/cc/resources/resource_provider.h
+++ b/cc/resources/resource_provider.h
@@ -332,6 +332,7 @@ class CC_EXPORT ResourceProvider {
     offscreen_context_provider_ = offscreen_context_provider;
   }
   static GLint GetActiveTextureUnit(WebKit::WebGraphicsContext3D* context);
+  bool use_16bit_textures() { return use_16bit_textures_; }
 
  private:
   struct Resource {
@@ -443,6 +444,8 @@ class CC_EXPORT ResourceProvider {
 
   scoped_refptr<Fence> current_read_lock_fence_;
 
+  bool use_16bit_textures_;
+
   DISALLOW_COPY_AND_ASSIGN(ResourceProvider);
 };