mf/scheme_handler: Split file scheme handler to scheme_handler.c.

dlls/mf/Makefile.in

@@ -13,6 +13,7 @@ C_SRCS = \
 	quality.c \
 	samplegrabber.c \
 	sar.c \
+	scheme_handler.c \
 	session.c \
 	topology.c \
 	topology_loader.c

dlls/mf/mf_private.h

@@ -113,6 +113,8 @@ static inline const char *debugstr_propvar(const PROPVARIANT *v)
     }
 }
 
+extern HRESULT file_scheme_handler_construct(REFIID riid, void **obj);
+
 extern BOOL mf_is_sample_copier_transform(IMFTransform *transform);
 extern BOOL mf_is_sar_sink(IMFMediaSink *sink);
 extern HRESULT topology_node_get_object(IMFTopologyNode *node, REFIID riid, void **obj);