qtest.h: actually include qtest_widgets.h

Was including qtest_gui.h instead, for QT_WIDGETS_LIB.

Not a problem in practice, since qtest_widgets.h doesn't
currently add anything on top of qtest_gui.h. But that will
change soon.

Change-Id: I942870cddc7b1ccfda262e2fe26834594336dd0b
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
QSizePolicy: add Q_FLAGS(ControlTypes)

There's no reason not to have it, and it allows better debug output.

[ChangeLog][QtWidgets][QSizePolicy] QSizePolicy::ControlTypes is now
introspectable through QSizePolicy's meta object.

Change-Id: Ia274c708f31e735e4605bd4769aa65a9b78d690f
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
tst_QSizePolicy: minor cleanup

Fix indention, remove unused functions, slots->Q_SLOTS.

Change-Id: I30ced40dcde2650977424864399b721bbe17013c
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
tst_QSizePolicy: split a test function

Split off default-value check from getSetCheck().

This is in preparation of extracting getSetCheck_data().

Change-Id: I869c34014a92e29a07dc08584a93a4cbba372518
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
tst_QSizePolicy: non-functional fixes

Fix indention, add empty line as separator, undef a local macro.

Change-Id: Ie0d8529322f87ca2bdedb9a7f2f4cf9f463a6e12
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>