QHash: fix compilation with gcc-4.2.1 (Mac OS X)

The anonymous union isn't supported and can be replaced with a reinterpret_cast.

Change-Id: Ic76a31f36e61d910db16312d7a6c4bdc728aa825
Reviewed-by: Thorbjørn Lund Martsum <tmartsum@gmail.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
QComboBox - only react on a mouse-release if we had a mousepress

In delegates we get into trouble with calling showPopup in
setEditorData (edit by double click) - and that is not reasonable.
The user has requested edit - and therefore it is natural to save
a click for the user and show the popup at once.

However that fails since we have the mouse down and as soon as we
release the mouse we will call hidePopup.

This patch ensures that the mouseReleaseEvent, that caused the
problem is only considered if we have had a mousePressEvent.

Change-Id: Ibe031fcb9ad2158f6969e41127bbb5f651b9cae6
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
configure: Check for Xrender only when building for XCB.

The XCB platform plugin is the only one that requires Xrender.

Change-Id: Iac2efa31b4b51e38305ee5f635fe38b75c7752de
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Mark qFuzzy* and qIsNull as Q_REQUIRED_RESULT

Calling them and not using the return value makes no sense.
And it's even worse -- in autotests people might call those
functions without wrapping them in QVERIFY(), effectively
not testing anything.

Change-Id: I2c90d1c85963ff1f35f00653d536a9252c2fcc48
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>