Revamp qmlvideo example

In order to make the example adhere to our example guidelines,
and to encourage the use of QML best practices. I've made numerous
improvements in this patch. Which contains the following changes.

- All root and context properties are replaced with a singleton.
- User facing strings are wrapped with qsTr().
- QtQuick.Controls buttons are now used, instead of the homemade
  Button.qml.
- We're now using colors from the palette, instead of hard coded color values.
- QtQuick.Layouts are now used, where it makes sense.
- Most qmllint warnings are now fixed, with a few being suppressed with
  qmllint enable/disable comments.

Fixes: QTBUG-113689
Pick-to: 6.7
Change-Id: I685d68665657f631cba4d8f83519ca2ecc45e2d8
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

1 files changed, 0 insertions, 2 deletions

diff --git a/examples/multimedia/video/qmlvideo/qmlvideo/VideoResize.qml b/examples/multimedia/video/qmlvideo/qmlvideo/VideoResize.qml
index a530d96b7..88fe7a2d2 100644
--- a/examples/multimedia/video/qmlvideo/qmlvideo/VideoResize.qml
+++ b/examples/multimedia/video/qmlvideo/qmlvideo/VideoResize.qml
@@ -1,8 +1,6 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
-import QtQuick
-
 SceneResize {
     contentType: "video"
 }