Convert utility process ImageWriter IPC to mojo

chrome/common/extensions/BUILD.gn

 # Copyright 2016 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("//build/config/features.gni")
 import("//extensions/features/features.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//tools/json_schema_compiler/json_features.gni")
 
 assert(enable_extensions)
 
 json_features("extension_features_unittest") {
   feature_type = "APIFeature"
   provider_class = "UnittestFeatureProvider"
   sources = [
     "//chrome/test/data/extensions/extension_api_unittest/api_features.json",
   ]
 }
 
 group("test_features") {
   public_deps = [
     ":extension_features_unittest",
   ]
 }
 
 mojom("mojo_bindings") {
   sources = [
     "media_parser.mojom",
+    "removable_storage_writer.mojom",
   ]
 
   if (is_win) {
     sources += [ "wifi_credentials_getter.mojom" ]
   }
 
   public_deps = [
     "//mojo/common:common_custom_types",
   ]
 }