Introduced a few more signals to QQuickWindow.

Also marked the new afterAnimation() signal as \since 5.3 and
introduced proper revisioning on the new signals.

[Changelog][QtQuick] Added QQuickWindow::afterSynchronizing(),
openglContextCreated(), sceneGraphAboutToStop(). Useful for
deeper integration with the rendering.

Change-Id: I5532b310506c2432325595e55ef9307b8934abee
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
Fix crashes and incorrect extension queries on GL3+

glGetString(GL_EXTENSIONS) is deprecated in OpenGL 3.0+.
This means that in core profiles on 3.2+ (or without the fwd
compatibility bit on 3.0/3.1), the call is not supported and may
return NULL. This causes a crash in at least one place where we
try to blindly strstr the result. The correct solution is to use
QOpenGLContext::extensions() and hasExtension() which is prepared
to handle GL3+.

Change-Id: I52fec7dcee001cdc0933af03f5eed4b7c822b2bb
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Add support for scanning javascript files.

Javascript may contain ".import" pragmas/statements,
which should be treated in a similar way as qml file
imports.

Add findQmlImportsInJavascriptFile() which extracts and
parses the .import lines. Refactor findQmlImportsInFile()
to handle both .qml and .js and call out to the correct
parsing function.

Add "-jsFiles" for specifying javascript
files on the command line similar to "-qmlFiles".

Task-number: QTBUG-35349

Change-Id: I6b8e0cc254c1edcf16940bec5cfda7c2637f115e
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
tst_qquickpathview: show window before flicking

It's uncertain whether this caused any actual CI failures, but other
tests show the window first, and this one tests interactive
functionality so it makes sense that it should be visible.

Change-Id: I92c26ce596f556765917409ca4e9037bdaccfa23
Reviewed-by: Jani Heikkinen <jani.heikkinen@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>