Add a method to tab_utils.h to find out whether a tab is playing audio.

chrome/browser/media/media_internals.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 "chrome/browser/media/media_internals.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/string16.h"
 #include "base/stringprintf.h"
+#include "chrome/browser/media/audio_stream_indicator.h"
 #include "chrome/browser/media/media_capture_devices_dispatcher.h"
 #include "chrome/browser/media/media_internals_observer.h"
 #include "chrome/browser/media/media_stream_capture_indicator.h"
 #include "chrome/browser/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_ui.h"
 #include "media/base/media_log.h"
 #include "media/base/media_log_event.h"
@@ skipping 64 matching lines @@
 
 MediaInternals::~MediaInternals() {}
 
 void MediaInternals::OnDeleteAudioStream(void* host, int stream_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   std::string stream = base::StringPrintf("audio_streams.%p:%d",
                                           host, stream_id);
   DeleteItem(stream);
 }
 
-void MediaInternals::OnSetAudioStreamPlaying(
-    void* host, int stream_id, bool playing) {
+void MediaInternals::OnSetAudioStreamPlaying(void* host,
+                                             int stream_id,
+                                             int render_process_id,
+                                             int render_view_id,
+                                             bool playing) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   UpdateAudioStream(host, stream_id,
                     "playing", Value::CreateBooleanValue(playing));
+  audio_stream_indicator_->UpdateWebContentsStatus(render_process_id,
+                                                  render_view_id,

[miu, 2012/12/19 00:49:08]

fix indentation.

+                                                  playing);
 }
 
 void MediaInternals::OnSetAudioStreamStatus(
     void* host, int stream_id, const std::string& status) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   UpdateAudioStream(host, stream_id,
                     "status", Value::CreateStringValue(status));
 }
 
 void MediaInternals::OnSetAudioStreamVolume(
@@ skipping 83 matching lines @@
 scoped_refptr<MediaCaptureDevicesDispatcher>
 MediaInternals::GetMediaCaptureDevicesDispatcher() {
   return media_devices_dispatcher_;
 }
 
 scoped_refptr<MediaStreamCaptureIndicator>
 MediaInternals::GetMediaStreamCaptureIndicator() {
   return media_stream_capture_indicator_.get();
 }
 
+AudioStreamIndicator* MediaInternals::GetAudioStreamIndicator() {
+  return audio_stream_indicator_;
+}
+
 MediaInternals::MediaInternals()
     : media_stream_capture_indicator_(new MediaStreamCaptureIndicator()),
-      media_devices_dispatcher_(new MediaCaptureDevicesDispatcher()) {
+      media_devices_dispatcher_(new MediaCaptureDevicesDispatcher()),
+      audio_stream_indicator_(new AudioStreamIndicator()) {
 }
 
 void MediaInternals::UpdateAudioStream(
     void* host, int stream_id, const std::string& property, Value* value) {
   std::string stream = base::StringPrintf("audio_streams.%p:%d",
                                           host, stream_id);
   UpdateItem("media.addAudioStream", stream, property, value);
 }
 
 void MediaInternals::DeleteItem(const std::string& item) {
@@ skipping 17 matching lines @@
 
 void MediaInternals::SendUpdate(const std::string& function, Value* value) {
   // Only bother serializing the update to JSON if someone is watching.
   if (observers_.size()) {
     std::vector<const Value*> args;
     args.push_back(value);
     string16 update = content::WebUI::GetJavascriptCall(function, args);
     FOR_EACH_OBSERVER(MediaInternalsObserver, observers_, OnUpdate(update));
   }
 }