libmediaplayerservice: fix warnings, make warnings errors, use clang

Change-Id: I1b2f6b65c5abbc366068a60b8909104f31b94228
diff --git a/media/libmediaplayerservice/MediaPlayerService.h b/media/libmediaplayerservice/MediaPlayerService.h
index 2a95ce1..6ddfe14 100644
--- a/media/libmediaplayerservice/MediaPlayerService.h
+++ b/media/libmediaplayerservice/MediaPlayerService.h
@@ -304,7 +304,7 @@
                                        int ext1, int ext2, const Parcel *obj);
 
                 pid_t           pid() const { return mPid; }
-        virtual status_t        dump(int fd, const Vector<String16>& args) const;
+        virtual status_t        dump(int fd, const Vector<String16>& args);
 
                 int             getAudioSessionId() { return mAudioSessionId; }