diff --git a/dom/media/gtest/MockMediaResource.h b/dom/media/gtest/MockMediaResource.h
index 7e3a13a3d0d0..1b0f53c173a4 100644
--- a/dom/media/gtest/MockMediaResource.h
+++ b/dom/media/gtest/MockMediaResource.h
@@ -38,7 +38,7 @@ public:
     return NS_OK;
   }
   virtual nsresult ReadAt(int64_t aOffset, char* aBuffer, uint32_t aCount,
-                          uint32_t* aBytes);
+                          uint32_t* aBytes) MOZ_OVERRIDE;
   virtual nsresult Seek(int32_t aWhence, int64_t aOffset) MOZ_OVERRIDE
   {
     return NS_OK;
@@ -57,7 +57,7 @@ public:
   virtual bool IsSuspendedByCache() MOZ_OVERRIDE { return false; }
   virtual bool IsSuspended() MOZ_OVERRIDE { return false; }
   virtual nsresult ReadFromCache(char* aBuffer, int64_t aOffset,
-                                 uint32_t aCount)
+                                 uint32_t aCount) MOZ_OVERRIDE
   {
     return NS_OK;
   }
diff --git a/dom/media/webrtc/MediaEngineTabVideoSource.h b/dom/media/webrtc/MediaEngineTabVideoSource.h
index ae4b3abb979d..10a781c20797 100644
--- a/dom/media/webrtc/MediaEngineTabVideoSource.h
+++ b/dom/media/webrtc/MediaEngineTabVideoSource.h
@@ -18,27 +18,27 @@ class MediaEngineTabVideoSource : public MediaEngineVideoSource, nsIDOMEventList
     NS_DECL_NSITIMERCALLBACK
     MediaEngineTabVideoSource();
 
-    virtual void GetName(nsAString_internal&);
-    virtual void GetUUID(nsAString_internal&);
+    virtual void GetName(nsAString_internal&) MOZ_OVERRIDE;
+    virtual void GetUUID(nsAString_internal&) MOZ_OVERRIDE;
     virtual nsresult Allocate(const VideoTrackConstraintsN &,
-                              const mozilla::MediaEnginePrefs&);
-    virtual nsresult Deallocate();
-    virtual nsresult Start(mozilla::SourceMediaStream*, mozilla::TrackID);
-    virtual void SetDirectListeners(bool aHasDirectListeners) {};
+                              const mozilla::MediaEnginePrefs&) MOZ_OVERRIDE;
+    virtual nsresult Deallocate() MOZ_OVERRIDE;
+    virtual nsresult Start(mozilla::SourceMediaStream*, mozilla::TrackID) MOZ_OVERRIDE;
+    virtual void SetDirectListeners(bool aHasDirectListeners) MOZ_OVERRIDE {};
     virtual void NotifyPull(mozilla::MediaStreamGraph*, mozilla::SourceMediaStream*, mozilla::TrackID, mozilla::StreamTime) MOZ_OVERRIDE;
-    virtual nsresult Stop(mozilla::SourceMediaStream*, mozilla::TrackID);
-    virtual nsresult Config(bool, uint32_t, bool, uint32_t, bool, uint32_t, int32_t);
-    virtual bool IsFake();
-    virtual const MediaSourceType GetMediaSource() {
+    virtual nsresult Stop(mozilla::SourceMediaStream*, mozilla::TrackID) MOZ_OVERRIDE;
+    virtual nsresult Config(bool, uint32_t, bool, uint32_t, bool, uint32_t, int32_t) MOZ_OVERRIDE;
+    virtual bool IsFake() MOZ_OVERRIDE;
+    virtual const MediaSourceType GetMediaSource() MOZ_OVERRIDE {
       return MediaSourceType::Browser;
     }
     virtual bool SatisfiesConstraintSets(
-      const nsTArray<const dom::MediaTrackConstraintSet*>& aConstraintSets)
+      const nsTArray<const dom::MediaTrackConstraintSet*>& aConstraintSets) MOZ_OVERRIDE
     {
       return true;
     }
 
-    virtual nsresult TakePhoto(PhotoCallback* aCallback)
+    virtual nsresult TakePhoto(PhotoCallback* aCallback) MOZ_OVERRIDE
     {
       return NS_ERROR_NOT_IMPLEMENTED;
     }
diff --git a/dom/media/webspeech/synth/ipc/SpeechSynthesisChild.h b/dom/media/webspeech/synth/ipc/SpeechSynthesisChild.h
index d7aca74e8a2a..994c9eaae56f 100644
--- a/dom/media/webspeech/synth/ipc/SpeechSynthesisChild.h
+++ b/dom/media/webspeech/synth/ipc/SpeechSynthesisChild.h
@@ -82,11 +82,11 @@ public:
 
   NS_IMETHOD SendAudioNative(int16_t* aData, uint32_t aDataLen) MOZ_OVERRIDE;
 
-  virtual void Pause();
+  virtual void Pause() MOZ_OVERRIDE;
 
-  virtual void Resume();
+  virtual void Resume() MOZ_OVERRIDE;
 
-  virtual void Cancel();
+  virtual void Cancel() MOZ_OVERRIDE;
 
 private:
   SpeechSynthesisRequestChild* mActor;
diff --git a/dom/media/webspeech/synth/nsSpeechTask.cpp b/dom/media/webspeech/synth/nsSpeechTask.cpp
index 99ca4edae0df..b01bdce192e7 100644
--- a/dom/media/webspeech/synth/nsSpeechTask.cpp
+++ b/dom/media/webspeech/synth/nsSpeechTask.cpp
@@ -68,7 +68,7 @@ public:
     }
   }
 
-  virtual void NotifyBlockingChanged(MediaStreamGraph* aGraph, Blocking aBlocked)
+  virtual void NotifyBlockingChanged(MediaStreamGraph* aGraph, Blocking aBlocked) MOZ_OVERRIDE
   {
     if (aBlocked == MediaStreamListener::UNBLOCKED && !mStarted) {
       mStarted = true;