Added a command line flag that disables force-compositing-mode and modified the about:flags entry t…

content/browser/web_contents/web_contents_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/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
@@ skipping 439 matching lines @@
   prefs.show_composited_layer_tree =
       command_line.HasSwitch(switches::kShowCompositedLayerTree);
   prefs.show_fps_counter =
       command_line.HasSwitch(switches::kShowFPSCounter);
   prefs.show_paint_rects =
       command_line.HasSwitch(switches::kShowPaintRects);
   prefs.accelerated_compositing_enabled =
       GpuProcessHost::gpu_enabled() &&
       !command_line.HasSwitch(switches::kDisableAcceleratedCompositing);
   prefs.force_compositing_mode =
-      command_line.HasSwitch(switches::kForceCompositingMode);
+      command_line.HasSwitch(switches::kForceCompositingMode) &&
+      !command_line.HasSwitch(switches::kDisableForceCompositingMode);
   prefs.fixed_position_compositing_enabled =
       command_line.HasSwitch(switches::kEnableCompositingForFixedPosition);
   prefs.accelerated_2d_canvas_enabled =
       GpuProcessHost::gpu_enabled() &&
       !command_line.HasSwitch(switches::kDisableAccelerated2dCanvas);
   prefs.deferred_2d_canvas_enabled =
       !command_line.HasSwitch(switches::kDisableDeferred2dCanvas);
   prefs.accelerated_painting_enabled =
       GpuProcessHost::gpu_enabled() &&
       command_line.HasSwitch(switches::kEnableAcceleratedPainting);
@@ skipping 2562 matching lines @@
       browser_plugin_host()->embedder_render_process_host();
   *embedder_container_id = browser_plugin_host()->instance_id();
   int embedder_process_id =
       embedder_render_process_host ? embedder_render_process_host->GetID() : -1;
   if (embedder_process_id != -1) {
     *embedder_channel_name =
         StringPrintf("%d.r%d", render_view_host->GetProcess()->GetID(),
                      embedder_process_id);
   }
 }