Position close buttons in bubbles based on a layout delegate constant.

ui/views/views_delegate.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_VIEWS_DELEGATE_H_
 #define UI_VIEWS_VIEWS_DELEGATE_H_
 
 #include <string>
 
 #if defined(OS_WIN)
@@ skipping 200 matching lines @@
 
   // Returns the insets that should be applied around a dialog's frame view.
   virtual gfx::Insets GetDialogFrameViewInsets();
 
   // Returns the margins that should be applied around a bubble dialog.
   virtual gfx::Insets GetBubbleDialogMargins();
 
   // Returns the padding that should be placed around a button's content.
   virtual gfx::Insets GetButtonPadding() const;
 
+  // Returns the distance between a dialog's edge and the close button in the
+  // upper trailing corner.
+  virtual int GetCloseButtonMargin() const;

[sky, 2017/02/01 16:55:07]

'close button' is rather generic, and it seems the current value is only
applicable to bubbles/dialogs. How about GetDialogCloseButtonMargin?

[Peter Kasting, 2017/02/07 04:45:29]

SGTM

+
  protected:
   ViewsDelegate();
 
  private:
   std::unique_ptr<ViewsTouchEditingControllerFactory> views_tsc_factory_;
 
 #if defined(USE_AURA)
   std::unique_ptr<TouchSelectionMenuRunnerViews> touch_selection_menu_runner_;
 #endif
 
   NativeWidgetFactory native_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewsDelegate);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_VIEWS_DELEGATE_H_