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

ui/ozone/platform/cast/ozone_platform_cast.cc

Index: ui/ozone/platform/cast/ozone_platform_cast.cc
diff --git a/ui/ozone/platform/cast/ozone_platform_cast.cc b/ui/ozone/platform/cast/ozone_platform_cast.cc
index 60f7c9a901220a23d2ed3f2662da1cdb6a714211..4134af08d7078ae06b7cde3829fac8f21106c50c 100644
--- a/ui/ozone/platform/cast/ozone_platform_cast.cc
+++ b/ui/ozone/platform/cast/ozone_platform_cast.cc
@@ -15,6 +15,7 @@
 #include "ui/ozone/public/cursor_factory_ozone.h"
 #include "ui/ozone/public/gpu_platform_support_host.h"
 #include "ui/ozone/public/input_controller.h"
+#include "ui/ozone/public/native_pixmap_manager.h"
 #include "ui/ozone/public/ozone_platform.h"
 #include "ui/ozone/public/system_input_injector.h"
 
@@ -102,4 +103,8 @@ OzonePlatform* CreateOzonePlatformCast() {
   return new OzonePlatformCast(platform.Pass());
 }
 
+NativePixmapManager* CreateNativePixmapManagerCast() {
+  return CreateStubNativePixmapManager();
+}
+
 }  // namespace ui