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

ui/views/controls/scrollbar/overlay_scroll_bar.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/controls/scrollbar/overlay_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 12 matching lines @@
 const int kThumbDefaultAlpha = 64;
 
 class OverlayScrollBarThumb : public BaseScrollBarThumb,
                               public gfx::AnimationDelegate {
  public:
   explicit OverlayScrollBarThumb(BaseScrollBar* scroll_bar);
   virtual ~OverlayScrollBarThumb();
 
  protected:
   // View overrides:
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
 
   // gfx::AnimationDelegate overrides:
   virtual void AnimationProgressed(const gfx::Animation* animation) OVERRIDE;
 
  private:
   double animation_opacity_;
   DISALLOW_COPY_AND_ASSIGN(OverlayScrollBarThumb);
 };
 
 OverlayScrollBarThumb::OverlayScrollBarThumb(BaseScrollBar* scroll_bar)
     : BaseScrollBarThumb(scroll_bar),
       animation_opacity_(0.0) {
   // This is necessary, otherwise the thumb will be rendered below the views if
   // those views paint to their own layers.
   SetPaintToLayer(true);
   SetFillsBoundsOpaquely(false);
 }
 
 OverlayScrollBarThumb::~OverlayScrollBarThumb() {
 }
 
-gfx::Size OverlayScrollBarThumb::GetPreferredSize() {
+gfx::Size OverlayScrollBarThumb::GetPreferredSize() const {
   return gfx::Size(kThumbMinimumSize, kThumbMinimumSize);
 }
 
 void OverlayScrollBarThumb::OnPaint(gfx::Canvas* canvas) {
   gfx::Rect local_bounds(GetLocalBounds());
   SkPaint paint;
   int alpha = kThumbDefaultAlpha * animation_opacity_;
   if (GetState() == CustomButton::STATE_HOVERED) {
     alpha = kThumbHoverAlpha * animation_opacity_;
   } else if(GetState() == CustomButton::STATE_PRESSED) {
@@ skipping 64 matching lines @@
     case ui::ET_SCROLL_FLING_START:
     case ui::ET_GESTURE_END:
       animation_.Hide();
       break;
     default:
       break;
   }
   BaseScrollBar::OnGestureEvent(event);
 }
 
-gfx::Size OverlayScrollBar::GetPreferredSize() {
+gfx::Size OverlayScrollBar::GetPreferredSize() const {
   return gfx::Size();
 }
 
 void OverlayScrollBar::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 OverlayScrollBar::OnPaint(gfx::Canvas* canvas) {
 }
 
 }  // namespace views