Add GetMinimumSize() for Borders, and make LabelButton auto-size to at least as

ui/views/border.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_BORDER_H_
 #define UI_VIEWS_BORDER_H_
 
 #include "base/basictypes.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/insets.h"
@@ skipping 50 matching lines @@
 
   // Creates a Border from the specified Painter. The border owns the painter,
   // thus the painter is deleted when the Border is deleted.
   // |insets| define size of an area allocated for a Border.
   static Border* CreateBorderPainter(Painter* painter,
                                      const gfx::Insets& insets);
 
   // Renders the border for the specified view.
   virtual void Paint(const View& view, gfx::Canvas* canvas) = 0;
 
-  // Sets the specified insets to the the border insets.
+  // Returns the border insets.
   virtual gfx::Insets GetInsets() const = 0;
 
+  // Returns the minimum size this border requires.  Note that this may not be

[msw, 2013/11/22 18:00:25]

Would it make sense to have the default Border::GetMinimumSize implementation
just return the size of the insets? That'd be sufficient for
ash/system/tray/tray_details_view.cc and in probably most other cases.

[Peter Kasting, 2013/11/22 22:07:55]

That's not the intent of GetMinimumSize() from Border's perspective.  That would
be appropriate for GetMinimumSize() on the view that has this border as a
border.  See other similar comments.

+  // the same as the insets.  For example, a Border may paint images to draw
+  // some graphical border around a view, and this would return the minimum size
+  // such that these images would not be clipped or overlapping -- but the
+  // insets may be larger or smaller, depending on how the view wanted its
+  // content laid out relative to these images.
+  virtual gfx::Size GetMinimumSize() const = 0;
+
   // Manual RTTI for text buttons.
   virtual TextButtonBorder* AsTextButtonBorder();
   virtual const TextButtonBorder* AsTextButtonBorder() const;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Border);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_BORDER_H_