Add command line switches and about:flag to enable FPS indicator and compositor layer tree.

chrome/browser/tab_contents/render_view_host_delegate_helper.cc

Index: chrome/browser/tab_contents/render_view_host_delegate_helper.cc
diff --git a/chrome/browser/tab_contents/render_view_host_delegate_helper.cc b/chrome/browser/tab_contents/render_view_host_delegate_helper.cc
index 79037472fdc657e92066f4c4dda3c5955ab8afad..29b4768a2840eed5754e156e8be0bdfbca7f5ab4 100644
--- a/chrome/browser/tab_contents/render_view_host_delegate_helper.cc
+++ b/chrome/browser/tab_contents/render_view_host_delegate_helper.cc
@@ -285,6 +285,10 @@ WebPreferences RenderViewHostDelegateHelper::GetWebkitPrefs(
         command_line.HasSwitch(switches::kAllowFileAccessFromFiles);
     web_prefs.show_composited_layer_borders =
         command_line.HasSwitch(switches::kShowCompositedLayerBorders);
+    web_prefs.show_composited_layer_tree =
+        command_line.HasSwitch(switches::kShowCompositedLayerTree);
+    web_prefs.show_fps_counter =
+        command_line.HasSwitch(switches::kShowFPSCounter);
     web_prefs.accelerated_compositing_enabled =
         gpu_enabled() &&
         !command_line.HasSwitch(switches::kDisableAcceleratedCompositing);