Use compositor_frame typemap in Blink

skia/public/interfaces/BUILD.gn

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//mojo/public/tools/bindings/mojom.gni")
 
 mojom("interfaces") {
   sources = [
     "bitmap.mojom",
     "image_filter.mojom",
@@ skipping 19 matching lines @@
     "test/traits_test_service.mojom",
   ]
 
   public_deps = [
     ":interfaces",
     ":mojo",
   ]
 
   use_new_wrapper_types = false
 }
+
+group("struct_traits") {

[yzshen1, 2016/09/01 00:02:54]

Can we delete this and rename struct_traits_sources to struct_traits?

+  public_deps = [
+    ":struct_traits_sources",
+  ]
+}
+
+source_set("struct_traits_sources") {
+  sources = [
+    "image_filter_struct_traits.cc",
+    "image_filter_struct_traits.h",
+  ]
+  public_deps = [
+    ":interfaces_shared_cpp_sources",
+    "//skia",
+  ]
+}