Adding a Views scrollbar implementation.

views/controls/scrollbar/native_scroll_bar_gtk.cc

 // Copyright (c) 2009 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 "views/controls/scrollbar/native_scroll_bar_gtk.h"
 
 #include <gtk/gtk.h>
 
 #include "ui/base/keycodes/keyboard_codes_posix.h"
 #include "views/controls/scrollbar/native_scroll_bar.h"
+#include "views/controls/scrollbar/native_scroll_bar_views.h"
 #include "views/controls/scrollbar/scroll_bar.h"
+#include "views/widget/widget.h"
 
 namespace views {
 
 ////////////////////////////////////////////////////////////////////////////////
 // NativeScrollBarGtk, public:
 
 NativeScrollBarGtk::NativeScrollBarGtk(NativeScrollBar* scroll_bar)
     : NativeControlGtk(),
       native_scroll_bar_(scroll_bar) {
   set_focus_view(scroll_bar);
@@ skipping 170 matching lines @@
   GtkAdjustment* adj = gtk_range_get_adjustment(GTK_RANGE(native_view()));
   MoveTo(adj->upper);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // NativewScrollBarWrapper, public:
 
 // static
 NativeScrollBarWrapper* NativeScrollBarWrapper::CreateWrapper(
     NativeScrollBar* scroll_bar) {
+  if (Widget::IsPureViews())
+    return new NativeScrollBarViews(scroll_bar);
   return new NativeScrollBarGtk(scroll_bar);
 }
 
 // static
 int NativeScrollBarWrapper::GetHorizontalScrollBarHeight() {
   // TODO(oshima): get this from gtk's widget property "slider-width".
   return 20;
 }
 
 // static
 int NativeScrollBarWrapper::GetVerticalScrollBarWidth() {
   // TODO(oshima): get this from gtk's widget property "slider-width".
   return 20;
 }
 
 }  // namespace views