MacViews: Reveal scrollbars when resting on the trackpad.

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 397 matching lines @@
   controller()->ScrollToPosition(this, position);
 }
 
 int BaseScrollBar::GetScrollIncrement(bool is_page, bool is_positive) {
   return controller()->GetScrollIncrement(this, is_page, is_positive);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // BaseScrollBar, private:
 
+#if !defined(OS_MACOSX)
+// static
+base::Timer* BaseScrollBar::GetHideTimerForTest(BaseScrollBar* scroll_bar) {
+  return nullptr;
+}
+#endif
+
 int BaseScrollBar::GetThumbSizeForTest() {
   return thumb_->GetSize();
 }
 
 void BaseScrollBar::ProcessPressEvent(const ui::LocatedEvent& event) {
   gfx::Rect thumb_bounds = thumb_->bounds();
   if (IsHorizontal()) {
     if (GetMirroredXInView(event.x()) < thumb_bounds.x()) {
       last_scroll_amount_ = SCROLL_PREV_PAGE;
     } else if (GetMirroredXInView(event.x()) > thumb_bounds.right()) {
@@ skipping 42 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