Reformat QOpenGL2PaintEngineExPrivate a bit to make it easier to refactor

Change-Id: I99f7192008ae8ea3a16f5300e5e4ebdde50847af
Reviewed-by: Laszlo Agocs <laszlo.agocs@theqtcompany.com>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@theqtcompany.com>
QMacStyle: Fix 32-bit build

Again one of those CGRect vs. NSRect issues.

Change-Id: Ia933cd6f002585e21247d2f9f85d2451db6dbaa0
Reviewed-by: Jake Petroules <jake.petroules@petroules.com>
Reviewed-by: Timur Pocheptsov <Timur.Pocheptsov@digia.com>
Fix QOpenGLWidget/QQuickWidget GUI freeze

A window with a renderToTexture child uses the OpenGL path, but when
we open a popup or dialog, that uses the raster compositor, which opens
a separate surface. This patch fixes two issues when combining GL rendering
with the raster compositor:

1. GL-rendered widgets were counted as part of the raster-rendered region,
meaning that we did not punch a hole in the raster surface.

2. We did not destroy the surface when no longer needed.

Task-number: QTBUG-41467
Change-Id: I2a2a0e860cce065b330df1c864d51fd02103aa1b
Reviewed-by: Christian Stromme <christian.stromme@theqtcompany.com>
Reviewed-by: BogDan Vatra <bogdan@kde.org>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@theqtcompany.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@theqtcompany.com>
Make no_debug_info also strip out -gstabs

Since QtWebKit started using stabs on some platforms to reducing
memory pressure during linking, the tricks to strip out debug-info
in the internals no longer worked because no-debug-info doesn't strip
the -gstabs compiler and linker flags.

Change-Id: I151088f29058b8fe50cba9aa3ec8ecd84b85d7d8
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>