WeakPtr destruction order cleanup: media edition.

media/video/capture/mac/video_capture_device_mac.h

Index: media/video/capture/mac/video_capture_device_mac.h
diff --git a/media/video/capture/mac/video_capture_device_mac.h b/media/video/capture/mac/video_capture_device_mac.h
index b672409b8c36b5f6307f181a30f8b3946e9496b5..7b1070a5ae571b3ea9cc296f592abb01bdbfff92 100644
--- a/media/video/capture/mac/video_capture_device_mac.h
+++ b/media/video/capture/mac/video_capture_device_mac.h
@@ -72,13 +72,13 @@ class VideoCaptureDeviceMac : public VideoCaptureDevice {
   const scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   InternalState state_;
 
-  // Used with Bind and PostTask to ensure that methods aren't called
-  // after the VideoCaptureDeviceMac is destroyed.
-  base::WeakPtrFactory<VideoCaptureDeviceMac> weak_factory_;
-  base::WeakPtr<VideoCaptureDeviceMac> weak_this_;
-
   id<PlatformVideoCapturingMac> capture_device_;
 
+  // Used with Bind and PostTask to ensure that methods aren't called after the
+  // VideoCaptureDeviceMac is destroyed.  NOTE: This must always be last so it's
+  // invalidated before other member variables might be accessed.
+  base::WeakPtrFactory<VideoCaptureDeviceMac> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(VideoCaptureDeviceMac);
 };