Revert "Preprocessor Enginge: fix bug in pp-engine.cpp"

Breaks highlighting for macros using the predefined macros.

This reverts commit 1d834c1126dde58dd71e595b3f5e135cc0ca4dbd.

Change-Id: Ic13c407e293a806a63ff30153864530df6a32e47
Reviewed-by: hjk <hjk121@nokiamail.com>
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>
C++: Fix highlighting for lines with predefined macros

This adds definitions for the macros __FILE__, __LINE__, __DATE__ and
__TIME__ on demand.

As a side effect, this also introduces highlighting for the uses of
these macros.

Task-number: QTCREATORBUG-8036
Change-Id: Ib7546c7d45d2eecbc50c7883fc684e3497154405
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>