Improving the appearance of overlay scrollbars

ui/views/controls/scrollbar/base_scroll_bar.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/scrollbar/base_scroll_bar.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
@@ skipping 382 matching lines @@
   thumb_->SetLength(static_cast<int>(ratio * GetTrackSize()));
 
   int thumb_position = CalculateThumbPosition(contents_scroll_offset);
   thumb_->SetPosition(thumb_position);
 }
 
 int BaseScrollBar::GetPosition() const {
   return thumb_->GetPosition();
 }
 
+bool BaseScrollBar::OverlapsContent() const {
+  return false;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // BaseScrollBar, protected:
 
 BaseScrollBarThumb* BaseScrollBar::GetThumb() const {
   return thumb_;
 }
 
 void BaseScrollBar::ScrollToPosition(int position) {
   controller()->ScrollToPosition(this, position);
 }
@@ skipping 67 matching lines @@
   int track_size = GetTrackSize();
   if (track_size == thumb_size)
     return 0;
   if (scroll_to_middle)
     thumb_position = thumb_position - (thumb_size / 2);
   return (thumb_position * (contents_size_ - viewport_size_)) /
          (track_size - thumb_size);
 }
 
 }  // namespace views