Improve logging related to start/stop and failure of audio input streams in Chrome

content/browser/renderer_host/media/audio_input_sync_writer.cc

 // Copyright (c) 2012 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 "content/browser/renderer_host/media/audio_input_sync_writer.h"
 
 #include <algorithm>
 
 #include "base/memory/shared_memory.h"
 #include "content/browser/renderer_host/media/media_stream_manager.h"
@@ skipping 38 matching lines @@
   socket_->Send(&bytes, sizeof(bytes));
 }
 
 void AudioInputSyncWriter::Write(const media::AudioBus* data,
                                  double volume,
                                  bool key_pressed) {
 #if !defined(OS_ANDROID)
   static const base::TimeDelta kLogDelayThreadhold =
       base::TimeDelta::FromMilliseconds(500);
 
   std::ostringstream oss;

[DaleCurtis, 2014/08/26 20:09:29]

Hmm, since this is called at a high frequency you should move this into a
function that is only called when oss will be updated.

[henrika (OOO until Aug 14), 2014/08/27 13:54:38]

Sorry, not sure if I follow. I have not changed anything here just some plain
text changes. Not sure what you propose actually and what it would save. Care to
elaborate?

The if (!oss.str().empty()) {} scope will only be triggered under error
conditions.

   if (last_write_time_.is_null()) {
     // This is the first time Write is called.
     base::TimeDelta interval = base::Time::Now() - creation_time_;
-    oss << "Audio input data received for the first time: delay = "
-        << interval.InMilliseconds() << "ms.";
+    oss << "AISW::Write => audio input data received for the first time: delay "
+           "= " << interval.InMilliseconds() << "ms";
 
   } else {
     base::TimeDelta interval = base::Time::Now() - last_write_time_;
     if (interval > kLogDelayThreadhold) {
-      oss << "Audio input data delay unexpectedly long: delay = "
-          << interval.InMilliseconds() << "ms.";
+      oss << "AISW::Write => audio input data delay unexpectedly long: delay = "
+          << interval.InMilliseconds() << "ms";
     }
   }
-  if (!oss.str().empty())
+  if (!oss.str().empty()) {
     MediaStreamManager::SendMessageToNativeLog(oss.str());
+    DVLOG(1) << oss.str();
+  }
 
   last_write_time_ = base::Time::Now();
 #endif
 
   // Write audio parameters to shared memory.
   uint8* ptr = static_cast<uint8*>(shared_memory_->memory());
   ptr += current_segment_id_ * shared_memory_segment_size_;
   media::AudioInputBuffer* buffer =
       reinterpret_cast<media::AudioInputBuffer*>(ptr);
   buffer->params.volume = volume;
@@ skipping 37 matching lines @@
     base::ProcessHandle process_handle,
     base::FileDescriptor* foreign_handle) {
   foreign_handle->fd = foreign_socket_->handle();
   foreign_handle->auto_close = false;
   return (foreign_handle->fd != -1);
 }
 
 #endif
 
 }  // namespace content