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 d1bdf278749d2276c289f10362f69a4a6798469c..3b12d83a2c5f40fa4d42e04b61698b17f129f826 100644
--- a/media/video/capture/mac/video_capture_device_mac.h
+++ b/media/video/capture/mac/video_capture_device_mac.h
@@ -76,13 +76,13 @@ 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: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<VideoCaptureDeviceMac> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(VideoCaptureDeviceMac);
 };