Allow MessageFilters to restrict listening to specific message classes

content/browser/renderer_host/media/audio_input_renderer_host.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_renderer_host.h"
 
 #include "base/bind.h"
 #include "base/memory/shared_memory.h"
 #include "base/metrics/histogram.h"
 #include "base/process/process.h"
 #include "content/browser/media/media_internals.h"
 #include "content/browser/renderer_host/media/audio_input_device_manager.h"
 #include "content/browser/renderer_host/media/audio_input_sync_writer.h"
 #include "content/browser/renderer_host/media/media_stream_manager.h"
 #include "content/browser/renderer_host/media/web_contents_audio_input_stream.h"
 #include "content/browser/renderer_host/media/web_contents_capture_util.h"
 #include "media/audio/audio_manager_base.h"
 
 namespace content {
+namespace {
+const uint32 kFilteredMessageClasses[] = {
+  AudioMsgStart,
+};
+}
 
 struct AudioInputRendererHost::AudioEntry {
   AudioEntry();
   ~AudioEntry();
 
   // The AudioInputController that manages the audio input stream.
   scoped_refptr<media::AudioInputController> controller;
 
   // The audio input stream ID in the render view.
   int stream_id;
@@ skipping 17 matching lines @@
       pending_close(false) {
 }
 
 AudioInputRendererHost::AudioEntry::~AudioEntry() {}
 
 AudioInputRendererHost::AudioInputRendererHost(
     media::AudioManager* audio_manager,
     MediaStreamManager* media_stream_manager,
     AudioMirroringManager* audio_mirroring_manager,
     media::UserInputMonitor* user_input_monitor)
-    : audio_manager_(audio_manager),
+    : BrowserMessageFilter(
+          kFilteredMessageClasses, arraysize(kFilteredMessageClasses)),
+      audio_manager_(audio_manager),
       media_stream_manager_(media_stream_manager),
       audio_mirroring_manager_(audio_mirroring_manager),
       user_input_monitor_(user_input_monitor),
       audio_log_(MediaInternals::GetInstance()->CreateAudioLog(
           media::AudioLogFactory::AUDIO_INPUT_CONTROLLER)) {}
 
 AudioInputRendererHost::~AudioInputRendererHost() {
   DCHECK(audio_entries_.empty());
 }
 
@@ skipping 348 matching lines @@
   // TODO(hclam): Implement a faster look up method.
   for (AudioEntryMap::iterator i = audio_entries_.begin();
        i != audio_entries_.end(); ++i) {
     if (controller == i->second->controller.get())
       return i->second;
   }
   return NULL;
 }
 
 }  // namespace content