Change Aura overlay scrollbars from solid color to painted scrollbars.

content/browser/renderer_host/render_view_host_impl.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 "content/browser/renderer_host/render_view_host_impl.h"
 
 #include <set>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 446 matching lines @@
       command_line.HasSwitch(switches::kDisable2dCanvasAntialiasing);
   prefs.antialiased_clips_2d_canvas_enabled =
       !command_line.HasSwitch(switches::kDisable2dCanvasClipAntialiasing);
   prefs.accelerated_2d_canvas_msaa_sample_count =
       atoi(command_line.GetSwitchValueASCII(
       switches::kAcceleratedCanvas2dMSAASampleCount).c_str());
 
   prefs.inert_visual_viewport =
       command_line.HasSwitch(switches::kInertVisualViewport);
 
-  prefs.use_solid_color_scrollbars = ui::IsOverlayScrollbarEnabled();
+  prefs.use_solid_color_scrollbars = false;
 
   prefs.history_entry_requires_user_gesture =
       command_line.HasSwitch(switches::kHistoryEntryRequiresUserGesture);
 
 #if defined(OS_ANDROID)
   // On Android, user gestures are normally required, unless that requirement
   // is disabled with a command-line switch or the equivalent field trial is
   // is set to "Enabled".
   const std::string autoplay_group_name = base::FieldTrialList::FindFullName(
       "MediaElementAutoplay");
   prefs.user_gesture_required_for_media_playback = !command_line.HasSwitch(
       switches::kDisableGestureRequirementForMediaPlayback) &&
           (autoplay_group_name.empty() || autoplay_group_name != "Enabled");
   prefs.autoplay_muted_videos_enabled =
       base::FeatureList::IsEnabled(features::kAutoplayMutedVideos);
 
   prefs.progress_bar_completion = GetProgressBarCompletionPolicy();
+
+  prefs.use_solid_color_scrollbars = true;
 #endif
 
   // Handle autoplay gesture override experiment.
   // Note that anything but a well-formed string turns the experiment off.
   prefs.autoplay_experiment_mode = base::FieldTrialList::FindFullName(
       "MediaElementGestureOverrideExperiment");
 
   prefs.touch_enabled = ui::AreTouchEventsEnabled();
   prefs.device_supports_touch = prefs.touch_enabled &&
       ui::GetTouchScreensAvailability() ==
@@ skipping 818 matching lines @@
     // Note: We are using the origin URL provided by the sender here. It may be
     // different from the receiver's.
     file_system_file.url =
         GURL(storage::GetIsolatedFileSystemRootURIString(
                  file_system_url.origin(), filesystem_id, std::string())
                  .append(register_name));
   }
 }
 
 }  // namespace content