Revert of MediaStream audio: Refactor 3 separate "glue" implementations into one.

content/renderer/media/media_stream_source.h

Index: content/renderer/media/media_stream_source.h
diff --git a/content/renderer/media/media_stream_source.h b/content/renderer/media/media_stream_source.h
index 7c451564d6f00bc514153e55c9d700ba29f81c5e..940efcc30a337da6d9e3957943766fda3b594251 100644
--- a/content/renderer/media/media_stream_source.h
+++ b/content/renderer/media/media_stream_source.h
@@ -9,7 +9,6 @@
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/macros.h"
-#include "base/threading/thread_checker.h"
 #include "content/common/content_export.h"
 #include "content/common/media/media_stream_options.h"
 #include "third_party/WebKit/public/platform/WebMediaStreamSource.h"
@@ -44,39 +43,36 @@
     return device_info_;
   }
 
-  // Stops the source (by calling DoStopSource()). This runs the
-  // |stop_callback_| (if set), and then sets the
-  // WebMediaStreamSource::readyState to ended.
+  // Stops the source (by calling DoStopSource()). This sets the
+  // WebMediaStreamSource::readyState to ended, triggers the |stop_callback_|
+  // if set. All pointers to this object are invalid after calling this.
   void StopSource();
+
+  void ResetSourceStoppedCallback() {
+    DCHECK(!stop_callback_.is_null());
+    stop_callback_.Reset();
+  }
+
+ protected:
+  // Called when StopSource is called. It allows derived classes to implement
+  // its  own Stop method.
+  virtual void DoStopSource() = 0;
 
   // Sets device information about a source that has been created by a
   // JavaScript call to GetUserMedia. F.E a camera or microphone.
-  void SetDeviceInfo(const StreamDeviceInfo& device_info);
+  void SetDeviceInfo(const StreamDeviceInfo& device_info) {
+    device_info_ = device_info;
+  }
 
   // Sets a callback that will be triggered when StopSource is called.
-  void SetStopCallback(const SourceStoppedCallback& stop_callback);
-
-  // Clears the previously-set SourceStoppedCallback so that it will not be run
-  // in the future.
-  void ResetSourceStoppedCallback();
-
- protected:
-  // Called when StopSource is called. It allows derived classes to implement
-  // its own Stop method.
-  virtual void DoStopSource() = 0;
+  void SetStopCallback(const SourceStoppedCallback& stop_callback) {
+    DCHECK(stop_callback_.is_null());
+    stop_callback_ = stop_callback;
+  }
 
  private:
-  // Called by both StopSource() and the destructor to ensure the
-  // |stop_callback_| has been run and the blink::WebMediaStreamSource's ready
-  // state has been set to "ended."
-  void RunStopCallbackAndEndStream();
-
   StreamDeviceInfo device_info_;
   SourceStoppedCallback stop_callback_;
-
-  // In debug builds, check that all methods are being called on the main
-  // thread.
-  base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamSource);
 };