Add Objective-C specific type converters to QByteArray

This patch adds the Objective-C NSData/CDataRef converters to
QByteArray

This will replace the current converters offered in QMacExtras

[ChangeLog][QtCore][Objective-C] Added NSData/CDataRef converters for
QByteArray

Change-Id: I7a0f14bee4271798db345f3c5efd26ac671a3ea4
Reviewed-by: Jake Petroules <jake.petroules@petroules.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Destroy backingstore before window

The window is created before the backingstore, so the destruction should
happen in the reverse order. Also, the backingstore is created based on
a pointer to a QWindow, so the dependency is from backingstore to window.
Thirdly, this fixes a crash when using QQuickWidget/QOpenGLWidget.

Task-number: QTBUG-37045
Change-Id: I6e782c553fddfeef877be30ca2610aff75a425a0
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
Improve code readability

Since we were requesting a multi font engine, the returned font engine
must be a multi one or nothing at all.

Change-Id: I1ee4e1b7c68f54c83a8c7292082d015ebfa0a8cb
Reviewed-by: Pierre Rossi <pierre.rossi@gmail.com>
Revert the QByteArrayList addition to Qt 5.3

This reverts commits f12b0f9a38c792abb13f3e6ecff4542986a6f96b
("QByteArrayList: optimize op+"),
f96f2fe3670bc8a32389795dc21b9839407465a1 ("Enable QByteArrayList
tests"), and 4f23f0530a9c59400a7f3821cd2c9355801ed8cd ("new
QByteArrayList class").

This class is coming back in Qt 5.4.

[ChangeLog][CHANGELOG FIX] Remove the line about QByteArrayList being
added.

Change-Id: I890ab2b34a9b3e575512eb306d0f241143a867cf
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>
Make Q_NULLPTR be NULL on C++98

Some compilers actually have a C++11-like null pointer constant in C++98
mode:

$ gcc -dM -E -include stddef.h -xc++ /dev/null | grep NULL
#define NULL __null
$ icc -dM -E -include stddef.h -xc++ /dev/null | grep NULL
#define NULL __null
$ clang -dM -E -include stddef.h -xc++ /dev/null | grep NULL
#define NULL __null

Change-Id: Ie0bcaf36fed6ad27e761a0a24332817129128571
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>