private Symbol getThunkedSymbol() {
		long thunkedFunctionId = functionMgr.getThunkedFunctionId(key);
		return (thunkedFunctionId >= 0) ? symbolMgr.getSymbol(thunkedFunctionId) : null;
	}
Construct a new FunctionSymbol
@param symbolMgr the symbol manager.
@param cache symbol object cache
@param address the address for this symbol.
@param record the record for this symbol.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/symbol/FunctionSymbol.java