Fix compile when QT_NO_WARNING_OUTPUT defined without QT_NO_DEBUG_STREAM

qWarning is forward declared as returning QDebug when QT_NO_DEBUG_STREAM
is not defined. This conflicts with the declaration of qWarning
returning QNoDebug when QT_NO_WARNING_OUTPUT is defined.

Avoid forward declaration of qWarning when QT_NO_WARNING_OUTPUT is not
defined to fix compilation.

This does not apply to Qt 5.

Task-number: QTBUG-33301
Change-Id: Ia4750cd63ac404700aedc36f07e5516d4163e9d2
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Test layout engine fundamentals

Done with Jan Arve

Task-number: QTBUG-33104

Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>
(cherry picked from qtbase/f3c019649ba99844b743a4b2ceb838aba86e7070)

Change-Id: I9bd761ea8c4de032b5a83a63ad65536697e80220
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>