void fallThroughChanged(Reference fallThroughRef) {
		if (!clearingFallThroughs) {
			Address fallThroughAddr = fallThroughRef != null ? fallThroughRef.getToAddress() : null;
			clearFallThroughRefs(fallThroughAddr); // ensure there is only one fallthrough ref
			if (fallThroughAddr == null) { // fallthrough ref removed
				setFallthroughOverride(false);
				addLengthOverrideFallthroughRef(); // restore length-override fallthrough if needed
			}
			else {
				// enable fallthrough-override if fallThroughRef does not match length-override fallthrough 
				setFallthroughOverride(!fallThroughAddr.equals(getLengthOverrideFallThrough()));
			}
		}
	}
Clear all existing fall-through references from address.
@param keepFallThroughAddr if not null, corresponding fall-through reference will be 
preserved.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/code/InstructionDB.java