ozone: Introduce ClientPixmap and ClientPixmapFactory for non-GPU processes.

ui/ozone/platform/drm/gbm_surface_factory.cc

Index: ui/ozone/platform/drm/gbm_surface_factory.cc
diff --git a/ui/ozone/platform/drm/gbm_surface_factory.cc b/ui/ozone/platform/drm/gbm_surface_factory.cc
index f81d74631b52d7eb40056a8426869f830cd2cdda..f963724803f56341eaa98565f731cdfdcf19897f 100644
--- a/ui/ozone/platform/drm/gbm_surface_factory.cc
+++ b/ui/ozone/platform/drm/gbm_surface_factory.cc
@@ -209,18 +209,6 @@ bool GbmSurfaceFactory::CanShowPrimaryPlaneAsOverlay() {
   return allow_surfaceless_;
 }
 
-bool GbmSurfaceFactory::CanCreateNativePixmap(BufferUsage usage) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  switch (usage) {
-    case MAP:
-      return false;
-    case SCANOUT:
-      return true;
-  }
-  NOTREACHED();
-  return false;
-}
-
 scoped_refptr<GbmDevice> GbmSurfaceFactory::GetGbmDevice(
     gfx::AcceleratedWidget widget) {
   return static_cast<GbmDevice*>(