AUDIO: Change several fake MidiDrivers to MidiDriver_BASE subclasses

Many engines follow the advice in audio/midiparser.h and create a
"pseudo-MidiDriver" subclass. But MidiParser really only needs a tiny
subset of the MidiDriver capabilities, namely those found in
MidiDriver_BASE. So we try to subclass from that whenever possible; this
allows us to remove many stub methods, and enables further future
simplifications.

1 files changed, 1 insertions, 12 deletions

diff --git a/engines/queen/music.h b/engines/queen/music.h
index 50f7b3d255..898abb42d9 100644
--- a/engines/queen/music.h
+++ b/engines/queen/music.h
@@ -39,7 +39,7 @@ struct TuneData;
 
 class QueenEngine;
 
-class MidiMusic : public MidiDriver {
+class MidiMusic : public MidiDriver_BASE {
 public:
 	MidiMusic(QueenEngine *vm);
 	~MidiMusic();
@@ -57,20 +57,9 @@ public:
 	void toggleVChange();
 
 	//MidiDriver interface implementation
-	int open() { return 0; }
-	bool isOpen() const { return true; }
-	void close() {}
 	void send(uint32 b);
-
 	void metaEvent(byte type, byte *data, uint16 length);
 
-	void setTimerCallback(void *timerParam, void (*timerProc)(void *)) { }
-	uint32 getBaseTempo()	{ return _driver ? _driver->getBaseTempo() : 0; }
-
-	//Channel allocation functions
-	MidiChannel *allocateChannel()		{ return 0; }
-	MidiChannel *getPercussionChannel()	{ return 0; }
-
 protected:
 
 	enum {