db/simple/Directory: RemoveSong() returns SongPtr

src/db/plugins/simple/Directory.cxx

@@ -172,7 +172,7 @@ Directory::AddSong(SongPtr song) noexcept
 	songs.push_back(*song.release());
 }
 
-void
+SongPtr
 Directory::RemoveSong(Song *song) noexcept
 {
 	assert(holding_db_lock());
@@ -180,6 +180,7 @@ Directory::RemoveSong(Song *song) noexcept
 	assert(&song->parent == this);
 
 	songs.erase(songs.iterator_to(*song));
+	return SongPtr(song);
 }
 
 const Song *

src/db/plugins/simple/Directory.hxx

@@ -257,9 +257,9 @@ public:
 	/**
 	 * Remove a song object from this directory (which effectively
 	 * invalidates the song object, because the "parent" attribute becomes
-	 * stale), but does not free it.
+	 * stale), and return ownership to the caller.
 	 */
-	void RemoveSong(Song *song) noexcept;
+	SongPtr RemoveSong(Song *song) noexcept;
 
 	/**
 	 * Caller must lock the #db_mutex.