Mojo: Use new message APIs to reduce copying

mojo/public/cpp/bindings/lib/interface_endpoint_client.cc

 // 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.
 
 #include "mojo/public/cpp/bindings/lib/interface_endpoint_client.h"
 
 #include <stdint.h>
 
 #include <utility>
 
@@ skipping 201 matching lines @@
   if (encountered_error_)
     return false;
 
   // Reserve 0 in case we want it to convey special meaning in the future.
   uint64_t request_id = next_request_id_++;
   if (request_id == 0)
     request_id = next_request_id_++;
 
   message->set_request_id(request_id);
 
+  bool is_sync = message->has_flag(kMessageIsSync);
   if (!controller_->SendMessage(message))
     return false;
 
-  if (!message->has_flag(kMessageIsSync)) {
+  if (!is_sync) {
     // We assume ownership of |responder|.
     async_responders_[request_id] = base::WrapUnique(responder);
     return true;
   }
 
   bool response_received = false;
   std::unique_ptr<MessageReceiver> sync_responder(responder);
   sync_responses_.insert(std::make_pair(
       request_id, base::WrapUnique(new SyncResponseInfo(&response_received))));
 
@@ skipping 66 matching lines @@
   } else {
     if (!incoming_receiver_)
       return false;
 
     return incoming_receiver_->Accept(message);
   }
 }
 
 }  // namespace internal
 }  // namespace mojo