Dialogs examples: remove QLayout::SetNoConstraint

These constraints were adjusted in qt4 commit 3abaecc in order to make
the dialogs fit Symbian/Maemo screens. These are not mobile oriented
examples and it breaks resizing behavior on desktop so badly, that
we will simply revert the constraint changes to make the dialogs
respect their minimum sizes.

Task-number: QTBUG-31351
Change-Id: Ibf358ddedadf05614ef7a66b6a98fe5d7073996f
Reviewed-by: Thorbjørn Lund Martsum <tmartsum@gmail.com>
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>
Reviewed-by: Caroline Chao <caroline.chao@digia.com>
Mac Accessibility: skip invisible children

Change-Id: I6c3da526ecef60447a658b6b5501282729e9c6f5
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>
Fix incorrect uname usage.

The POSIX function uname() can return any non-negative value for success.
- Example: Solaris 10 returns 1 on success.
See: http://pubs.opengroup.org/onlinepubs/009695399/functions/uname.html

Change-Id: Ic3d51f94a31d8b562b28a2d09df3d31b04c77dc8
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>