Rename Quick examples' folder from webengine to webenginequick

Fix webengine directory path in project files and comments

Change-Id: I06ed9ee41111e7135fa9feb152ad2a5eb2262b76
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
(cherry picked from commit a32ef7057c01fbcadcf451e7f2b785f7b3dd3942)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

4 files changed, 104 insertions, 0 deletions

diff --git a/examples/webenginequick/lifecycle/doc/images/lifecycle-automatic.png b/examples/webenginequick/lifecycle/doc/images/lifecycle-automatic.png
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diff --git a/examples/webenginequick/lifecycle/doc/images/lifecycle-manual.png b/examples/webenginequick/lifecycle/doc/images/lifecycle-manual.png
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diff --git a/examples/webenginequick/lifecycle/doc/images/lifecycle.png b/examples/webenginequick/lifecycle/doc/images/lifecycle.png
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diff --git a/examples/webenginequick/lifecycle/doc/src/lifecycle.qdoc b/examples/webenginequick/lifecycle/doc/src/lifecycle.qdoc
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+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+    \example webenginequick/lifecycle
+    \title WebEngine Lifecycle Example
+    \ingroup webengine-examples
+    \brief Freezes and discards background tabs to reduce CPU and memory usage.
+
+    \image lifecycle.png
+
+    \e {WebEngine Lifecycle Example} demonstrates how the \l
+    {WebEngineView::}{lifecycleState} and \l {WebEngineView::}{recommendedState}
+    properties of the \l {WebEngineView} can be used to reduce the CPU and
+    memory usage of background tabs in a tabbed browser.
+
+    For an overview of the lifecycle feature, see \l {Page Lifecycle API}.
+
+    \include examples-run.qdocinc
+
+    \section1 UI Elements of the Example
+
+    The example uses \l {Qt Quick Controls 2} to implement a traditional tabbed
+    browser in the \l {Material Style} (dark variant). The main application
+    window (\c {WebBrowser.qml}) is divided into a header bar at the top and a
+    main viewing area filling the rest of the window. The header contains the
+    tab bar (\c {WebTabBar.qml}) with one button per tab (\c
+    {WebTabButton.qml}). The main area consists of a stack of tabs (\c
+    {WebTabStack.qml} and \c {WebTab.qml}). Each tab in turn has a tool bar at
+    the top and a \l {WebEngineView} for displaying web pages. Finally, the main
+    window also has a \l {Drawer} for changing settings. The drawer can be
+    opened by clicking the "⋮" button on the tool bar.
+
+    \section1 Lifecycle States in the Example
+
+    The example implements two ways of changing the lifecycle state: manual and
+    automatic. The manual way uses the \l {WebEngineView::}{lifecycleState}
+    property directly to change the web view lifecycle state, while the
+    automatic way is timer-based and also takes into account the \l
+    {WebEngineView::}{recommendedState}.
+
+    The tab titles in the tab bar are color coded with frozen tabs shown in blue
+    and discarded in red.
+
+    \section2 Manual Lifecycle Control
+
+    \image lifecycle-manual.png
+
+    Manual control is provided by context menus on the tab bar buttons (\c
+    {WebTabButton.qml}). The menu has three radio buttons, one for each
+    lifecycle state, with the current state checked. Some buttons may be
+    disabled, either because they represent illegal state transitions (for
+    example, a \c {Discarded} view cannot directly transition to the \c {Frozen}
+    state), or because other preconditions are not fulfilled (for example, a
+    visible view can only be in the \c {Active} state).
+
+    \section2 Automatic Lifecycle Control
+
+    \image lifecycle-automatic.png
+
+    Automatic control is implemented with a \l {Timer} in the \c {WebTab}
+    component (\c {WebTab.qml}). The timer is started whenever the \l
+    {WebEngineView::}{lifecycleState} of the web view does not match it's \l
+    {WebEngineView::}{recommendedState}. Once the timer fires, the view's
+    lifecycle state is set to the recommended state.
+
+    The time delay is used to avoid changing the lifecycle state too quickly
+    when the user is switching between tabs. The freezing and discarding delays
+    can be changed in the settings drawer accessed through the "⋮" button on the
+    tool bar.
+
+    This is a rather simple algorithm for automatic lifecycle control, however
+    more sophisticated algorithms could also be conceived and implemented on the
+    basis of the \l {WebEngineView::}{lifecycleState} property. For example, the
+    Chromium browser experimentally uses a pretrained deep neural network to
+    predict the next tab activation time by the user, essentially ranking tabs
+    based on how interesting they are to the user. Implementing such an
+    algorithm is left as an exercise to the reader for now.
+
+*/