C++: remove warning about stray comma after last enumerator

Although it's a C++11 feature, all sane compilers support it as an
extension to C++03/C++98.

Change-Id: I3c7b0db345d0b175554534e879717f4d14f48b0f
Reviewed-by: hjk <hjk121@nokiamail.com>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>
C++: add test for TranslationUnit::getPosition bug

This test is marked as failing, because the bug is still there. To be
fixed when we re-use the generated token stream of the preprocessor as
input for the parser.

Task-number: QTCREATORBUG-9799
Change-Id: I454a9939aa188a6ff934a11699232f39c828bc7b
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>