Fix crash on startup when running screenreader

For exaple Qt Creator would crash when started and a screen reader (eg
NVDA) is running. This is due to updateAccessibility being called during
the ctor of the TextEdit and on Windows the AT can access properties in
the same call resulting in accessing the text control before it's fully
constructed.

Also make sure to not send accessibility updates for non-widget type edits
since we don't support any accessibility in Qt Quick 1.

Backported from Qt 5.3.1 since it also crashes Qt Creator on startup on
Mac (as soon as accessibility is enabled which may be for various
reasons, and basically any app that uses a QTextEdit).

Task-number: QTBUG-38659
Task-number: QTBUG-38738
Change-Id: I6e5c0dc47bd75e63fe013a9edadbabccd52c20ee
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>
Avoid using repeat on widget textures in eglfs

Otherwise widgets will not be shown on some embedded systems.

Task-number: QTBUG-38866
Change-Id: Id16408dc7eb657c052bbe3bdb86e35ab2f062632
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
Doc: Update the list of highlighted examples

Remove highlighting for examples with known problems, and
examples that don't work on all platforms. Add highlighting
for improved ones and prominent examples that demonstrate
new features.

Task-number: QTBUG-37203
Change-Id: Ida7fd28573dfebe6e4e3320ef83782654632219e
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>