views: support vertical-drag-to-end on textfields

ui/views/style/platform_style.h

 // Copyright 2015 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_STYLE_PLATFORM_STYLE_H_
 #define UI_VIEWS_STYLE_PLATFORM_STYLE_H_
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/views/controls/button/button.h"
@@ skipping 19 matching lines @@
   // custom default border is not provided for a particular LabelButton class.
   static scoped_ptr<LabelButtonBorder> CreateLabelButtonBorder(
       Button::ButtonStyle style);
 
   // Applies the current system theme to the default border created by |button|.
   static scoped_ptr<Border> CreateThemedLabelButtonBorder(LabelButton* button);
 
   // Creates the default scrollbar for the given orientation.
   static scoped_ptr<ScrollBar> CreateScrollBar(bool is_horizontal);
 
+  // True if dragging vertically above or below a textfield's bounds selects to
+  // the beginning or end of the text from the cursor, respectively.
+  static const bool kTextfieldDragVerticallyDragsToEnd;

[tapted, 2016/04/06 23:29:38]

this should be ordered before all the functions (see e.g.
http://crrev.com/1569113002/diff/470001/ui/views/style/platform_style.h where we
will git-conflict :p). order should be adjusted in the .cc's too

[Elly Fong-Jones, 2016/04/07 17:43:47]

Done.

+
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PlatformStyle);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_STYLE_PLATFORM_STYLE_H_