WeakPtr destruction order cleanup: media edition.

content/renderer/media/webaudiosourceprovider_impl.h

Index: content/renderer/media/webaudiosourceprovider_impl.h
diff --git a/content/renderer/media/webaudiosourceprovider_impl.h b/content/renderer/media/webaudiosourceprovider_impl.h
index d1a6fe723226eff398d3084acf91b991bd49f513..d8029afd1f6b2a1e6995a0da632b79a018e8c80d 100644
--- a/content/renderer/media/webaudiosourceprovider_impl.h
+++ b/content/renderer/media/webaudiosourceprovider_impl.h
@@ -56,8 +56,6 @@ class CONTENT_EXPORT WebAudioSourceProviderImpl
   // Calls setFormat() on |client_| from the Blink renderer thread.
   void OnSetFormat();
 
-  base::WeakPtrFactory<WebAudioSourceProviderImpl> weak_this_;
-
   // Closure that posts a task to call OnSetFormat() on the renderer thread.
   base::Closure set_format_cb_;
 
@@ -81,6 +79,10 @@ class CONTENT_EXPORT WebAudioSourceProviderImpl
   scoped_refptr<media::AudioRendererSink> sink_;
   scoped_ptr<media::AudioBus> bus_wrapper_;
 
+  // NOTE: This must always be last so it's invalidated before other member
+  // variables might be accessed.
+  base::WeakPtrFactory<WebAudioSourceProviderImpl> weak_this_;
+
   DISALLOW_IMPLICIT_CONSTRUCTORS(WebAudioSourceProviderImpl);
 };