Add initial build configuration for QNX.

QNX is using Ozone, so exclude gl_context_ozone as well.

Change-Id: Icdad9eed3211e9b095fbf884bc5e0243b551c1bb
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>
Reviewed-by: Arvid Nilsson <anilsson@blackberry.com>
Set the QtWebEngine modules version to 0.9.0

Also make sure that this version number appears in the user agent
string and in the QML imports. The plan, unlike other Qt modules,
is to keep our module and QML versions in sync to make it easy
for developers to figure out what API is available in a given version.

The QTWEBENGINECORE_VERSION_STR define is explicitly set in the .pro
file since we don't call syncqt to generate a version header for the
core module.

The 0-major version currently causes the library name to start with
libQt0 instead of libQt5, but this is something that we can fix in
qtbase once we want to officially support linux desktop with
QtWebEngine 1.0.0.

Change-Id: I31915e84869b4db456416ef1f85a2296b8a06c99
Reviewed-by: Pierre Rossi <pierre.rossi@gmail.com>
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Fix a crash preventing us from using ImplSidePainting

Because of an uninvestigated reason, ImplSidePainting can cause more
than one quad to use the same resource_id in one delegated frame.

Fix the issue by first checking if m_data->mailboxTextures contains
a texture for the resource_id before overwriting it.

This also re-enables the feature on OS_ANDROID where it is enabled by
default.

Change-Id: Ie7842f958e1c049db71ffc2a0a768a5725102a3d
Reviewed-by: Andras Becsi <andras.becsi@digia.com>
Remove the webpage snippet for now.

This snippet contains API that we might not support at all. It is
better to remove it and add a new version in case we reintroduce
this than to present a snippet that does not work or only works
partially.

Change-Id: Ia47ad69108ddcbe529aecff8e4f235b17d80514f
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>