Nativeparser class do much things which should not belong to.
such as "generate code suggesting list", this is also language specific, should lower to some other class like "c++ parser class".
I think the nativeparser should only manage different parser classes.
Also, CodeCompletion class has a lot of code doing the "ToolBar GUI control"(such as jump from function bodies...) but It shouldn't be there, either the toolbar related code can be grouped out to make a new class, or it should be lowered to a language specific class.