Remove the widget from the stylesheet cache before polishing

If the widget exists in the style rules cache before it polishes for the
first time then it should be removed from styleSheetCache too so that the
latest set stylesheet is used for the polishing.

Task-number: QTBUG-39427
Change-Id: Ic1e7988afe530f16ea9996bae56543ed554d6be9
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Do not overwrite existing event mask of root window

QXcbScreen installs its own event mask on the screen's root window.
This overwrites any existing event mask already set and by that
breaks applications when a new screen is added.

By first fetching the existing event mask and adding it to the newly
installed event mask, Qt does no longer break applications also
installing an event mask on the root window.

Task-number: QTBUG-39648
Change-Id: I8686dd6ae49d0e807c6fe1ea4a231ff728bfcf25
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
Reviewed-by: Uli Schlachter <psychon@znc.in>
Reviewed-by: Gatis Paeglis <gatis.paeglis@digia.com>
Properly check which OpenGL features are supported

QOpenGLShaderProgram::hasOpenGLShaderPrograms tests whether
QOpenGLFunctions::Shaders is provided for the given context. As the
initialization code assumed OpenGL 2 this always was true. But
unfortunately we still cannot assume that OpenGL 2 is universally
supported. E.g. indirect rendering (no matter how bad that idea is)
does not support OpenGL 2 on all hardware and the Shader related
extensions are not available.

This change makes sure that only when OpenGL 2 is available the
features provided by OpenGL 2 are enabled. If OpenGL 2 is not
available the extensions are tested. The checks are slightly
reordered to not do the extension tests at all if OpenGL 2 is
available.

Task-number: QTBUG-39730
Change-Id: Ic775163e0dcc519925b1287f3c4ca5e8ebf101d5
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
pass a pointer instead of a reference to initFrom()

msvc thinks that it's impossible to create a null reference (because
some language lawyer said so) and thus complains about our assert that
checks the reference's validity. work around by not dereferencing the
pointers we already have.

Change-Id: Ife2288d4187860105de12fdebc0e671e0159ace3
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
XCB: Fix leak with touch devices

Task-number: QTBUG-39596
Change-Id: I4225d5a1ab4939280640b35d30c283f056a56519
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
Correct QImage::fill(uint) on RGBA8888 formats

QImage::fill(uint) was incorrectly performing ARGB->RGBA conversion when
called on RGBA8888 formated images.

This patch moves the color conversion to QImage::fill(QColor) where it
belongs so that fill(uint) can behave consistent with documentation and
how it treats other formats.

The fill(uint) method had no automated tests, and this patch adds one.

[ChangeLog][QtGui][QImage] QImage::fill(uint) now fills the given pixel
value unconverted when used on RGBA8888 image, making it consistent with
the documentation and treatment of all other image formats.

Change-Id: I00a9d810c61d350dbdd7c4b9ad09e5ce11896b6d
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
QWindowsPrintDevice check for NULL pDevMode from PPRINTER_INFO_2

The MSDN documentation states that the pDevMode member of
PPRINTER_INFO_2 may be NULL.

Task-number: QTBUG-39764
Change-Id: I9c3a4bb565115415dbf45544f3d2391107356610
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>