Allow MediaExtractor to create FileSource

Remove binder call to MediaServer for reading files.

Test: Photos, Play Music, Play Movies, Youtube
Bug: 29125703
Change-Id: Id6abf592bf6d70b81158f6038b1982f0a537b9b9
diff --git a/services/mediaextractor/MediaExtractorService.h b/services/mediaextractor/MediaExtractorService.h
index 078af0c..9df3ecd 100644
--- a/services/mediaextractor/MediaExtractorService.h
+++ b/services/mediaextractor/MediaExtractorService.h
@@ -34,6 +34,9 @@
     static const char*  getServiceName() { return "media.extractor"; }
 
     virtual sp<IMediaExtractor> makeExtractor(const sp<IDataSource> &source, const char *mime);
+
+    virtual sp<IDataSource> makeIDataSource(int fd, int64_t offset, int64_t length);
+
     virtual status_t    dump(int fd, const Vector<String16>& args);
 
     virtual status_t    onTransact(uint32_t code, const Parcel& data, Parcel* reply,