Refactor Timer classes in preparation for landing FrameTimers.

third_party/WebKit/Source/modules/mediastream/MediaStream.cpp

Index: third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
diff --git a/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp b/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
index 2566a1eaff5896f4adf4f6b848ae822ba3605c3e..8545812f12f9fc25e4d28a70034a9ff69581c707 100644
--- a/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
+++ b/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
@@ -395,7 +395,7 @@ void MediaStream::scheduleDispatchEvent(Event* event)
         m_scheduledEventTimer.startOneShot(0, BLINK_FROM_HERE);
 }
 
-void MediaStream::scheduledEventTimerFired(Timer<MediaStream>*)
+void MediaStream::scheduledEventTimerFired(TimerBase*)
 {
     if (m_stopped)
         return;