rem: WindowLayer::DirtyRegion() { BRegion dirty; if (fDesktop->ReadLockClipping()) { dirty = *fDesktop->DirtyRegion(); fDesktop->ReadUnlockClipping(); } return dirty; }
add: inline	BRegion&				DirtyRegion() { return fDirtyRegion; }
context: WindowLayer::DirtyRegion(){	BRegion dirty;	if (fDesktop->ReadLockClipping()) {		dirty = *fDesktop->DirtyRegion();		fDesktop->ReadUnlockClipping();	}	return dirty;}