Ozone: Avoid blocking in Swapbuffer Call.

ui/ozone/platform/dri/gbm_surface_factory.cc

Index: ui/ozone/platform/dri/gbm_surface_factory.cc
diff --git a/ui/ozone/platform/dri/gbm_surface_factory.cc b/ui/ozone/platform/dri/gbm_surface_factory.cc
index ee227a14b7255a621f8b6665fbc255eb35b45574..bc67f231ef01c6c497d32a93f007a614241f3c02 100644
--- a/ui/ozone/platform/dri/gbm_surface_factory.cc
+++ b/ui/ozone/platform/dri/gbm_surface_factory.cc
@@ -15,6 +15,7 @@
 #include "ui/ozone/platform/dri/gbm_buffer.h"
 #include "ui/ozone/platform/dri/gbm_surface.h"
 #include "ui/ozone/platform/dri/gbm_surfaceless.h"
+#include "ui/ozone/platform/dri/page_flip_event_handler.h"
 #include "ui/ozone/platform/dri/screen_manager.h"
 #include "ui/ozone/public/native_pixmap.h"
 #include "ui/ozone/public/overlay_candidates_ozone.h"
@@ -128,8 +129,13 @@ GbmSurfaceFactory::CreateSurfacelessEGLSurfaceForWidget(
   if (!allow_surfaceless_)
     return scoped_ptr<SurfaceOzoneEGL>();
 
+  if (!flip_handler_)
+    flip_handler_ =
+        scoped_ptr<PageFlipEventHandler>(new PageFlipEventHandler());
+
   DriWindowDelegate* delegate = GetOrCreateWindowDelegate(widget);
-  return scoped_ptr<SurfaceOzoneEGL>(new GbmSurfaceless(delegate));
+  return scoped_ptr<SurfaceOzoneEGL>(
+      new GbmSurfaceless(delegate, flip_handler_.get()));
 }
 
 scoped_refptr<ui::NativePixmap> GbmSurfaceFactory::CreateNativePixmap(