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

ui/ozone/platform/drm/gpu/gbm_surface_factory.h

Index: ui/ozone/platform/drm/gpu/gbm_surface_factory.h
diff --git a/ui/ozone/platform/drm/gpu/gbm_surface_factory.h b/ui/ozone/platform/drm/gpu/gbm_surface_factory.h
index 0bc01b3be4fb52b4bf5738f9df58f91573a40e36..9073a83f89823514a3b0890d9c74bc4a768a46d7 100644
--- a/ui/ozone/platform/drm/gpu/gbm_surface_factory.h
+++ b/ui/ozone/platform/drm/gpu/gbm_surface_factory.h
@@ -40,7 +40,6 @@ class GbmSurfaceFactory : public DrmSurfaceFactory {
       BufferFormat format,
       BufferUsage usage) override;
   bool CanShowPrimaryPlaneAsOverlay() override;
-  bool CanCreateNativePixmap(BufferUsage usage) override;
 
  private:
   scoped_refptr<GbmDevice> GetGbmDevice(gfx::AcceleratedWidget widget);