CppEditor: Fix tests indentation

Change-Id: I1a5d78af88719a5070fea387559e2e2863ea6aca
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>
CppTools: Avoid matching function by name only

Compare full function signature, or at least argument count.

Task-number: QTCREATORBUG-10295
Change-Id: Iead4d067209a8aea77cfcea2cd1ca5d08f87b165
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>