Add WindowPinType property on arua::Window

ui/views/widget/widget.h

Index: ui/views/widget/widget.h
diff --git a/ui/views/widget/widget.h b/ui/views/widget/widget.h
index 36b86eac93a87926d45778c7dc978709977252a0..6ed720a034e2b5157d87b188e866127ae82a0844 100644
--- a/ui/views/widget/widget.h
+++ b/ui/views/widget/widget.h
@@ -547,6 +547,9 @@ class VIEWS_EXPORT Widget : public internal::NativeWidgetDelegate,
   void SetFullscreen(bool fullscreen);
   bool IsFullscreen() const;
 
+  void Pin(bool trusted);

[sky, 2017/03/30 20:12:21]

Pinning is specific to ChromeOS, so you shouldn't expose functions for it at the
Widget level. Instead set the property on the widget's nativeview, e.g. the
aura::Window.

[Peng, 2017/03/30 21:10:11]

Done.

+  bool IsPinned() const;
+
   // Sets the opacity of the widget. This may allow widgets behind the widget
   // in the Z-order to become visible, depending on the capabilities of the
   // underlying windowing system.