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

ui/views/shadow_border.cc

 // Copyright 2013 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.
 
 #include "ui/views/shadow_border.h"
 
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/insets.h"
 #include "ui/gfx/shadow_value.h"
 #include "ui/gfx/skia_util.h"
@@ skipping 16 matching lines @@
 // poor performance. Ideally we should be caching the border to bitmaps.
 void ShadowBorder::Paint(const views::View& view, gfx::Canvas* canvas) {
   SkPaint paint;
   std::vector<gfx::ShadowValue> shadows;
   shadows.push_back(gfx::ShadowValue(gfx::Point(), blur_, color_));
   skia::RefPtr<SkDrawLooper> looper = gfx::CreateShadowDrawLooper(shadows);
   paint.setLooper(looper.get());
   paint.setColor(SK_ColorTRANSPARENT);
   paint.setStrokeJoin(SkPaint::kRound_Join);
   gfx::Rect bounds(view.size());
+  // TODO(pkasting): This isn't right if one of the offsets is larger than
+  // (blur_ / 2).
   bounds.Inset(gfx::Insets(blur_ / 2, blur_ / 2, blur_ / 2, blur_ / 2));
   canvas->DrawRect(bounds, paint);
 }
 
 gfx::Insets ShadowBorder::GetInsets() const {
   return gfx::Insets(blur_ / 2 - vertical_offset_,
                      blur_ / 2 - horizontal_offset_,
                      blur_ / 2 + vertical_offset_,
                      blur_ / 2 + horizontal_offset_);
 }
 
+gfx::Size ShadowBorder::GetMinimumSize() const {
+  return gfx::Size(blur_, blur_);
+}
+
 }  // namespace views