media: Add MediaOzonePlatform support

ui/ozone/ozone_platform.h

Index: ui/ozone/ozone_platform.h
diff --git a/ui/ozone/ozone_platform.h b/ui/ozone/ozone_platform.h
index 536ff0ed8e26e1182acde7e698293f7533f0e663..514883da0beff66beee71f25d56a6a350eb72abc 100644
--- a/ui/ozone/ozone_platform.h
+++ b/ui/ozone/ozone_platform.h
@@ -8,6 +8,11 @@
 #include "base/memory/scoped_ptr.h"
 #include "ui/ozone/ozone_export.h"
 
+// TODO(vignatti): is content layer here alright?
+namespace content {
+class VideoDecodeFactoryOzone;
+}
+
 namespace gfx {
 class SurfaceFactoryOzone;
 }
@@ -47,6 +52,8 @@ class OZONE_EXPORT OzonePlatform {
   // Factory getters to override in subclasses. The returned objects will be
   // injected into the appropriate layer at startup. Subclasses should not
   // inject these objects themselves. Ownership is retained by OzonePlatform.
+  virtual content::VideoDecodeFactoryOzone*
+      GetVideoDecodeFactoryOzone() = 0;
   virtual gfx::SurfaceFactoryOzone* GetSurfaceFactoryOzone() = 0;
   virtual ui::EventFactoryOzone* GetEventFactoryOzone() = 0;
   virtual ui::InputMethodContextFactoryOzone*