Added experiment for changing viewport scroll ordering.

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 421 matching lines @@
   prefs.accelerated_2d_canvas_msaa_sample_count =
       atoi(command_line.GetSwitchValueASCII(
       switches::kAcceleratedCanvas2dMSAASampleCount).c_str());
   // Text blobs rely on impl-side painting for proper LCD handling.
   prefs.text_blobs_enabled = command_line.HasSwitch(switches::kForceTextBlobs)
       || (content::IsImplSidePaintingEnabled() &&
           !command_line.HasSwitch(switches::kDisableTextBlobs));
 
   prefs.pinch_overlay_scrollbar_thickness = 10;
   prefs.use_solid_color_scrollbars = ui::IsOverlayScrollbarEnabled();
+  prefs.viewport_scroll_order_experiment =
+      command_line.HasSwitch(switches::kEnableViewportScrollOrderExperiment);
 
 #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");
@@ skipping 980 matching lines @@
     if (!policy->CanReadFile(GetProcess()->GetID(), file))
       policy->GrantReadFile(GetProcess()->GetID(), file);
   }
 }
 
 void RenderViewHostImpl::SelectWordAroundCaret() {
   Send(new ViewMsg_SelectWordAroundCaret(GetRoutingID()));
 }
 
 }  // namespace content