views: Make view::Views::GetPreferredSize() const.

ui/views/controls/throbber.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/throbber.h"
 
 #include "base/time/time.h"
 #include "grit/ui_resources.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas.h"
@@ skipping 50 matching lines @@
   frame_count_ = frames_->width() / frames_->height();
   PreferredSizeChanged();
 }
 
 void Throbber::Run() {
   DCHECK(running_);
 
   SchedulePaint();
 }
 
-gfx::Size Throbber::GetPreferredSize() {
+gfx::Size Throbber::GetPreferredSize() const {
   return gfx::Size(frames_->height(), frames_->height());
 }
 
 void Throbber::OnPaint(gfx::Canvas* canvas) {
   if (!running_ && !paint_while_stopped_)
     return;
 
   const TimeDelta elapsed_time = Time::Now() - start_time_;
   const int current_frame =
       static_cast<int>(elapsed_time / frame_time_) % frame_count_;
@@ skipping 77 matching lines @@
   }
   // Otherwise we paint our tick mark or nothing depending on our state.
   if (checked_) {
     int checkmark_x = (width() - checkmark_->width()) / 2;
     int checkmark_y = (height() - checkmark_->height()) / 2;
     canvas->DrawImageInt(*checkmark_, checkmark_x, checkmark_y);
   }
 }
 
 }  // namespace views