Done-with: Roberto Raggi

Fixed crash in FindUsages on a dirty file in a large project, which is saved
while the FindUsages is still running.

Fixes QTCREATORBUG-787

Reviewed-by: Erik Verbruggen

Task-number: QTCREATORBUG-577

call of overloaded ‘QString(int)’ is ambiguous

This reverts commit 2a59d2ae.

This reverts commit f4163b8b.

Because apparently, while designing the Objective-C language, somebody
thought it was a world-class idea to allow any white-space between the
'@' character and the subsequent keyword. With this fix, we now
correctly parse:
    @  dynamic
and:
    @
      selector
and:
    @"foo"
     "bar"
    @"mooze"
(This last one is 1 single string split over multiple lines.)
Wonderful, isn't it?

What we (and Clang) do not support, but what GCC supports is something
like:
   @"foo"@@  "bar"  @"mooze"  @@
which is equivalent to @"foobarmooze".

Task-number: QTCREATORBUG-643
Merge-request: 109
Reviewed-by: Thorbjørn Lindeijer <thorbjorn.lindeijer@nokia.com>

doing it in 1.3 as well to avoid possible later conflicts