mediaplayer: ensure secure decoders are instantiated before starting source

Bug: 19984798
Change-Id: Iff13cf03c4ce3141380f4d7ab4a2b1045c5ce747
diff --git a/media/libmediaplayerservice/nuplayer/GenericSource.h b/media/libmediaplayerservice/nuplayer/GenericSource.h
index 385d73a..2d73ea9 100644
--- a/media/libmediaplayerservice/nuplayer/GenericSource.h
+++ b/media/libmediaplayerservice/nuplayer/GenericSource.h
@@ -96,6 +96,7 @@
         kWhatStopWidevine,
         kWhatStart,
         kWhatResume,
+        kWhatSecureDecodersInstantiated,
     };
 
     struct Track {
@@ -161,6 +162,9 @@
     status_t prefillCacheIfNecessary();
 
     void notifyPreparedAndCleanup(status_t err);
+    void onSecureDecodersInstantiated(status_t err);
+    void finishPrepareAsync();
+    status_t startSources();
 
     void onGetFormatMeta(sp<AMessage> msg) const;
     sp<MetaData> doGetFormatMeta(bool audio) const;