Add --root-layer-scrolls.

content/public/common/content_switches.cc

Index: content/public/common/content_switches.cc
diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
index ce240d443bb36287eae514b9cd553eae4a192fb2..a85c90bbbcad3dd2ef2a6b37ee3af8f7049e2901 100644
--- a/content/public/common/content_switches.cc
+++ b/content/public/common/content_switches.cc
@@ -715,6 +715,9 @@ const char kRendererProcessLimit[]          = "renderer-process-limit";
 // Causes the renderer process to display a dialog on launch.
 const char kRendererStartupDialog[]         = "renderer-startup-dialog";
 
+// Handles frame scrolls via the root RenderLayer instead of the FrameView.
+const char kRootLayerScrolls[]              = "root-layer-scrolls";
+
 // Causes the process to run as a sandbox IPC subprocess.
 const char kSandboxIPCProcess[]             = "sandbox-ipc";