views: implement dialog width snapping

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 <memory>
 #include <string>
 
@@ skipping 62 matching lines @@
 };
 
 enum class DistanceMetric {
   // The default padding to add on each side of a button's label.
   BUTTON_HORIZONTAL_PADDING,
   // The distance between a dialog's edge and the close button in the upper
   // trailing corner.
   CLOSE_BUTTON_MARGIN,
   // The default minimum width of a dialog button.
   DIALOG_BUTTON_MINIMUM_WIDTH,
+  // Dialog widths are snapped upwards to a multiple of this unit.
+  DIALOG_WIDTH_SNAPPING_UNIT,
   // The spacing between a pair of related horizontal buttons, used for
   // dialog layout.
   RELATED_BUTTON_HORIZONTAL,
   // Horizontal spacing between controls that are logically related.
   RELATED_CONTROL_HORIZONTAL,
   // The spacing between a pair of related vertical controls, used for
   // dialog layout.
   RELATED_CONTROL_VERTICAL,
 };
 
@@ skipping 172 matching lines @@
 #endif
 
   NativeWidgetFactory native_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewsDelegate);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_VIEWS_DELEGATE_H_