Enable pinch & scrollbars by default for CrOS.

content/renderer/gpu/render_widget_compositor.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 "content/renderer/gpu/render_widget_compositor.h"
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 164 matching lines @@
         settings.top_controls_hide_threshold = hide_threshold;
   }
 
   settings.partial_swap_enabled = widget->AllowPartialSwap() &&
       cmd->HasSwitch(cc::switches::kEnablePartialSwap);
   settings.background_color_instead_of_checkerboard =
       cmd->HasSwitch(cc::switches::kBackgroundColorInsteadOfCheckerboard);
   settings.show_overdraw_in_tracing =
       cmd->HasSwitch(cc::switches::kTraceOverdraw);
 
+#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_CHROMEOS)
+  settings.use_pinch_zoom_scrollbars =
+      cmd->HasSwitch(cc::switches::kEnablePinchZoomScrollbars);
+#endif
+
   // These flags should be mirrored by UI versions in ui/compositor/.
   settings.initial_debug_state.show_debug_borders =
       cmd->HasSwitch(cc::switches::kShowCompositedLayerBorders);
   settings.initial_debug_state.show_fps_counter =
       cmd->HasSwitch(cc::switches::kShowFPSCounter);
   settings.initial_debug_state.show_paint_rects =
       cmd->HasSwitch(switches::kShowPaintRects);
   settings.initial_debug_state.show_platform_layer_tree =
       cmd->HasSwitch(cc::switches::kShowCompositedLayerTree);
   settings.initial_debug_state.show_property_changed_rects =
@@ skipping 357 matching lines @@
   return RenderThreadImpl::current()->OffscreenContextProviderForMainThread();
 }
 
 scoped_refptr<cc::ContextProvider>
 RenderWidgetCompositor::OffscreenContextProviderForCompositorThread() {
   return RenderThreadImpl::current()->
       OffscreenContextProviderForCompositorThread();
 }
 
 }  // namespace content