Don't allow software fallback for UI compositor on CrOS

content/browser/aura/gpu_process_transport_factory.cc

Index: content/browser/aura/gpu_process_transport_factory.cc
diff --git a/content/browser/aura/gpu_process_transport_factory.cc b/content/browser/aura/gpu_process_transport_factory.cc
index ee92513397e9b74d25d08dec66e377a6a02db106..38dc904ccc9c3586d5e2a3d898ca50a4fbde2af1 100644
--- a/content/browser/aura/gpu_process_transport_factory.cc
+++ b/content/browser/aura/gpu_process_transport_factory.cc
@@ -185,6 +185,11 @@ scoped_ptr<cc::OutputSurface> GpuProcessTransportFactory::CreateOutputSurface(
 
   scoped_refptr<ContextProviderCommandBuffer> context_provider;
 
+  // Software fallback does not happen on Chrome OS.
+#if defined(OS_CHROMEOS)
+  software_fallback = false;
+#endif
+
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   if (!command_line->HasSwitch(switches::kUIEnableSoftwareCompositing) &&
       !software_fallback) {