Add WindowPinType property on arua::Window

ui/views/widget/widget.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_WIDGET_WIDGET_H_
 #define UI_VIEWS_WIDGET_WIDGET_H_
 
 #include <map>
 #include <memory>
 #include <set>
@@ skipping 529 matching lines @@
   void Restore();
 
   // Whether or not the window is maximized or minimized.
   virtual bool IsMaximized() const;
   bool IsMinimized() const;
 
   // Accessors for fullscreen state.
   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.
   void SetOpacity(float opacity);
 
   // Flashes the frame of the window to draw attention to it. Currently only
   // implemented on Windows for non-Aura.
   void FlashFrame(bool flash);
 
   // Returns the View at the root of the View hierarchy contained by this
@@ skipping 428 matching lines @@
   bool movement_disabled_;
 
   ScopedObserver<ui::NativeTheme, ui::NativeThemeObserver> observer_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(Widget);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_WIDGET_H_