It fixes:
* highlighing
* find usage
* follow symbol

when function of class has the same name as:
* local variable
* template parameter
* other struct/union/class/enum
* function argument

in function scope.

Task-number: QTCREATORBUG-8902
Change-Id: Iddc0f764af689babb40d39460d174bac7b919b31
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Sergey Shambir <sergey.shambir.auto@gmail.com>
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>