mash: Add autoclick app.

ash/autoclick/common/autoclick_controller_common_delegate.h

Index: ash/autoclick/common/autoclick_controller_common_delegate.h
diff --git a/ash/autoclick/common/autoclick_controller_common_delegate.h b/ash/autoclick/common/autoclick_controller_common_delegate.h
index 12035386fad72014cce95cab1a4696b74a44cec8..7d09172aa618af6f89f012ab479d290115172ec2 100644
--- a/ash/autoclick/common/autoclick_controller_common_delegate.h
+++ b/ash/autoclick/common/autoclick_controller_common_delegate.h
@@ -24,7 +24,7 @@ class AutoclickControllerCommonDelegate {
 
   // Creates a ring widget at |event_location|. AutoclickControllerCommon

[sky, 2016/09/09 21:42:29]

Update comment? Also, it's not clear why you want to change the ownership
around. Can you explain why ownership should move to the delegate and not the
caller?

[riajiang, 2016/09/12 16:15:46]

Done. I think it makes more sense since the app (the delegate in mash mode) is
the one that is responsible for creating and closing the widget and it owns
AutoclickControllerCommon as well?

   // takes ownership of the created widget.
-  virtual std::unique_ptr<views::Widget> CreateAutoclickRingWidget(
+  virtual views::Widget* CreateAutoclickRingWidget(
       const gfx::Point& event_location) = 0;
 
   // Moves |widget| to |event_location|.