Cleanup: Pass std::string as const reference from media/

media/cast/test/sender.cc

 // Copyright 2013 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.
 
 // Test application that simulates a cast sender - Data can be either generated
 // or read from a file.
 
 #include <queue>
 
 #include "base/at_exit.h"
@@ skipping 89 matching lines @@
                                                   it->frame_id);
   }
 }
 
 void QuitLoopOnInitializationResult(media::cast::OperationalStatus result) {
   CHECK(result == media::cast::STATUS_INITIALIZED)
       << "Cast sender uninitialized";
   base::MessageLoop::current()->Quit();
 }
 
-net::IPEndPoint CreateUDPAddress(std::string ip_str, uint16 port) {
+net::IPEndPoint CreateUDPAddress(const std::string& ip_str, uint16 port) {
   net::IPAddressNumber ip_number;
   CHECK(net::ParseIPLiteralToNumber(ip_str, &ip_number));
   return net::IPEndPoint(ip_number, port);
 }
 
 void DumpLoggingData(const media::cast::proto::LogMetadata& log_metadata,
                      const media::cast::FrameEventList& frame_events,
                      const media::cast::PacketEventList& packet_events,
                      base::ScopedFILE log_file) {
   VLOG(0) << "Frame map size: " << frame_events.size();
@@ skipping 245 matching lines @@
                  base::Unretained(cast_sender.get()),
                  audio_config,
                  base::Bind(&QuitLoopOnInitializationResult)));
   io_message_loop.Run();  // Wait for audio initialization.
 
   fake_media_source->Start(cast_sender->audio_frame_input(),
                            cast_sender->video_frame_input());
   io_message_loop.Run();
   return 0;
 }