Remove device change deduplication based on device id.

media/audio/win/audio_device_listener_win.h

Index: media/audio/win/audio_device_listener_win.h
diff --git a/media/audio/win/audio_device_listener_win.h b/media/audio/win/audio_device_listener_win.h
index 9c2ac4824a67ebc92284fcbbc1eb9af7a87ddf99..de4c7dd6debcf68bead0deb9957a437788e393f4 100644
--- a/media/audio/win/audio_device_listener_win.h
+++ b/media/audio/win/audio_device_listener_win.h
@@ -11,6 +11,7 @@
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/threading/thread_checker.h"
+#include "base/time/time.h"
 #include "base/win/scoped_comptr.h"
 #include "media/base/media_export.h"
 
@@ -50,10 +51,9 @@ class MEDIA_EXPORT AudioDeviceListenerWin : public IMMNotificationClient {
 
   base::Closure listener_cb_;
   ScopedComPtr<IMMDeviceEnumerator> device_enumerator_;
-  std::string default_render_device_id_;
-  std::string default_capture_device_id_;
-  std::string default_communications_render_device_id_;
-  std::string default_communications_capture_device_id_;
+
+  // Used to rate limit device change events.
+  base::TimeTicks last_device_change_time_;
 
   // AudioDeviceListenerWin must be constructed and destructed on one thread.
   base::ThreadChecker thread_checker_;