cros login: Forward native GMB flags.

Forward native GMB command line flags for Guest session.

BUG=475633

Change-Id: Id92d8f0a871d3c4ed644d24bb1951be5410c1dac
Reviewed-on: https://chromium-review.googlesource.com/576456
Commit-Queue: Dongseong Hwang <dongseong.hwang@intel.com>
Reviewed-by: Dongseong Hwang <dongseong.hwang@intel.com>
Reviewed-by: Dan Erat <derat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#491220}

chrome/browser/chromeos/BUILD.gn

@@ -137,6 +137,7 @@ source_set("chromeos") {
     "//extensions/browser",
     "//extensions/browser/kiosk",
     "//gpu",
+    "//gpu/ipc/host:host",
     "//mash/public/interfaces",
     "//media",
     "//media/mojo/interfaces",

chrome/browser/chromeos/login/chrome_restart_request.cc

@@ -40,6 +40,7 @@
 #include "content/public/browser/browser_thread.h"
 #include "content/public/common/content_switches.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
+#include "gpu/ipc/host/gpu_switches.h"
 #include "gpu/ipc/service/switches.h"
 #include "media/base/media_switches.h"
 #include "media/media_features.h"
@@ -112,6 +113,7 @@ void DeriveCommandLine(const GURL& start_url,
     ::switches::kEnableGpuRasterization,
     ::switches::kEnableLogging,
     ::switches::kEnableLowResTiling,
+    ::switches::kEnableNativeGpuMemoryBuffers,
     ::switches::kDisablePartialRaster,
     ::switches::kEnablePartialRaster,
     ::switches::kEnablePinch,