[Media Router] Convert to use typemaps for media_router.mojom.

chrome/browser/media/router/route_request_result.cc

 // 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.
 
 #include "chrome/browser/media/router/route_request_result.h"
 
 #include "base/memory/ptr_util.h"
 #include "chrome/browser/media/router/media_route.h"
 
 namespace media_router {
 
 // static
 std::unique_ptr<RouteRequestResult> RouteRequestResult::FromSuccess(
-    std::unique_ptr<MediaRoute> route,
+    const MediaRoute& route,
     const std::string& presentation_id) {
-  DCHECK(route);
-  return base::WrapUnique(new RouteRequestResult(
-      std::move(route), presentation_id, "", RouteRequestResult::OK));
+  return base::MakeUnique<RouteRequestResult>(
+      base::MakeUnique<MediaRoute>(route), presentation_id, "",

[dcheng, 2017/02/01 22:51:08]

It feels weird that we pass this by unique_ptr: should we just pass by reference
directly?

[imcheng, 2017/02/02 21:20:37]

I wanted FromSuccess and FromError to invoke the same constructor so it has to
take a MediaRoute ptr.

+      RouteRequestResult::OK);
 }
 
 // static
 std::unique_ptr<RouteRequestResult> RouteRequestResult::FromError(
     const std::string& error,
     ResultCode result_code) {
-  return base::WrapUnique(
-      new RouteRequestResult(nullptr, "", error, result_code));
+  return base::MakeUnique<RouteRequestResult>(nullptr, "", error, result_code);

[dcheng, 2017/02/01 22:51:08]

Nit: "" should be std::string() here and above.

[imcheng, 2017/02/02 21:20:37]

Done.

 }
 
 RouteRequestResult::RouteRequestResult(std::unique_ptr<MediaRoute> route,
                                        const std::string& presentation_id,
                                        const std::string& error,
                                        ResultCode result_code)
     : route_(std::move(route)),
       presentation_id_(presentation_id),
       error_(error),
       result_code_(result_code) {
   if (route_)
     presentation_url_ = route_->media_source().url();
 }
 
 RouteRequestResult::~RouteRequestResult() = default;
 
 }  // namespace media_router