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

ui/views/controls/scrollbar/kennedy_scroll_bar.cc

 // Copyright (c) 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/controls/scrollbar/kennedy_scroll_bar.h"
 
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/gfx/canvas.h"
 #include "ui/views/background.h"
@@ skipping 10 matching lines @@
 const SkColor kThumbDefaultColor = SkColorSetARGB(64, 0, 0, 0);
 const SkColor kTrackHoverColor = SkColorSetARGB(32, 0, 0, 0);
 
 class KennedyScrollBarThumb : public BaseScrollBarThumb {
  public:
   explicit KennedyScrollBarThumb(BaseScrollBar* scroll_bar);
   virtual ~KennedyScrollBarThumb();
 
  protected:
   // View overrides:
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(KennedyScrollBarThumb);
 };
 
 KennedyScrollBarThumb::KennedyScrollBarThumb(BaseScrollBar* scroll_bar)
     : BaseScrollBarThumb(scroll_bar) {
 }
 
 KennedyScrollBarThumb::~KennedyScrollBarThumb() {
 }
 
-gfx::Size KennedyScrollBarThumb::GetPreferredSize() {
+gfx::Size KennedyScrollBarThumb::GetPreferredSize() const {
   return gfx::Size(kThumbMinimumSize, kThumbMinimumSize);
 }
 
 void KennedyScrollBarThumb::OnPaint(gfx::Canvas* canvas) {
   gfx::Rect local_bounds(GetLocalBounds());
   canvas->FillRect(local_bounds,
                    (GetState() == CustomButton::STATE_HOVERED ||
                     GetState() == CustomButton::STATE_PRESSED) ?
                    kThumbHoverColor : kThumbDefaultColor);
   canvas->DrawRect(local_bounds, kBorderColor);
@@ skipping 14 matching lines @@
   gfx::Size track_size = local_bounds.size();
   track_size.SetToMax(GetThumb()->size());
   local_bounds.set_size(track_size);
   return local_bounds;
 }
 
 int KennedyScrollBar::GetLayoutSize() const {
   return kScrollbarWidth;
 }
 
-gfx::Size KennedyScrollBar::GetPreferredSize() {
+gfx::Size KennedyScrollBar::GetPreferredSize() const {
   return GetTrackBounds().size();
 }
 
 void KennedyScrollBar::Layout() {
   gfx::Rect thumb_bounds = GetTrackBounds();
   BaseScrollBarThumb* thumb = GetThumb();
   if (IsHorizontal()) {
     thumb_bounds.set_x(thumb->x());
     thumb_bounds.set_width(thumb->width());
   } else {
     thumb_bounds.set_y(thumb->y());
     thumb_bounds.set_height(thumb->height());
   }
   thumb->SetBoundsRect(thumb_bounds);
 }
 
 void KennedyScrollBar::OnPaint(gfx::Canvas* canvas) {
   CustomButton::ButtonState state = GetThumbTrackState();
   if ((state == CustomButton::STATE_HOVERED) ||
       (state == CustomButton::STATE_PRESSED)) {
     gfx::Rect local_bounds(GetLocalBounds());
     canvas->FillRect(local_bounds, kTrackHoverColor);
     canvas->DrawRect(local_bounds, kBorderColor);
   }
 }
 
 }  // namespace views