CustomButton cleanup: make protected members private, create accessors

ui/views/controls/combobox/combobox.cc

 // 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.
 
 #include "ui/views/controls/combobox/combobox.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "ui/accessibility/ax_view_state.h"
@@ skipping 79 matching lines @@
     SetAnimationDuration(LabelButton::kHoverAnimationDurationMs);
   }
   ~TransparentButton() override {}
 
   bool OnMousePressed(const ui::MouseEvent& mouse_event) override {
     parent()->RequestFocus();
     return true;
   }
 
   double GetAnimationValue() const {
-    return hover_animation_->GetCurrentValue();
+    return hover_animation().GetCurrentValue();
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TransparentButton);
 };
 
 // Returns the next or previous valid index (depending on |increment|'s value).
 // Skips separator or disabled indices. Returns -1 if there is no valid adjacent
 // index.
 int GetAdjacentIndex(ui::ComboboxModel* model, int increment, int index) {
@@ skipping 811 matching lines @@
   return gfx::Size(width, font_list.GetHeight());
 }
 
 PrefixSelector* Combobox::GetPrefixSelector() {
   if (!selector_)
     selector_.reset(new PrefixSelector(this));
   return selector_.get();
 }
 
 }  // namespace views