Qt Quick Controls 2 was named that way because it was a follow-up to
Qt Quick Controls 1.x. Now that Qt Quick Controls 1 is no longer
supported, we don't need to have "2" in the name. Work on this was
already started for the documentation in
1abdfe5d5a052f2298b7bf657513dfa7e0c66a56.

By doing this renaming a few weeks before feature freeze, it won't
affect the release but still results in as little time possible spent
manually fixing conflicts in cherry-picks from non-LTS releases as a
result of the renaming.

This patch does the following:

- Renames directories.
- Adapts CMakeLists.txt and other files to account for the new paths.

A follow-up patch will handle documentation.

It does not touch library names or other user-facing stuff, as that
will have to be done in Qt 7.

Task-number: QTBUG-95413
Change-Id: I170d8db19033ee71e495ff0c5c1a517a41ed7634
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

This is a semantic patch using ClangTidyTransformator to convert
sequences of Q_UNREACHABLE() + return into Q_UNREACHABLE_RETURN(),
newly added to qtbase.

    const std::string unr = "unr", val = "val", ret = "ret";
    auto makeUnreachableReturn = cat("Q_UNREACHABLE_RETURN(",
                                    ifBound(val, cat(node(val)), cat("")),
                                    ")");
    auto ignoringSwitchCases = [](auto stmt) {
        return anyOf(stmt, switchCase(subStmt(stmt)));
    };

    makeRule(stmt(ignoringSwitchCases(stmt(isExpandedFromMacro("Q_UNREACHABLE")).bind(unr)),
                  nextStmt(returnStmt(optionally(hasReturnValue(expr().bind(val)))).bind(ret))),
             {changeTo(node(unr), cat(makeUnreachableReturn,
                                      ";")), // TODO: why is the ; lost w/o this?
              changeTo(node(ret), cat(""))},
             cat("use ", makeUnreachableReturn));

a.k.a qt-use-unreachable-return.

subStmt() and nextStmt() are non-standard matchers.

There was one false positive, suppressed it with NOLINTNEXTLINE.

It's not really a false positiive, it's just that Clang sees the world
in one way and if conditonal compilation (#if) differs for other
compilers, Clang doesn't know better. This is an artifact of matching
two consecutive statements.

Change-Id: I3855b2dc8523db1ea860f72ad9818738162495c6
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

This type has been used internally as QQuickAttachedObject by the
Imagine, Material and Universal styles to enable propagation of colors,
dark mode flags, etc. for a while now. Users would benefit from having
access to it to create their own styles (although it's not just limited
to that use case).

This patch:

- Makes the type public in quickcontrols2.
- Adds documentation and an example.
- Fixes the test_window test to ensure that propagation through child
  windows actually works.

[ChangeLog][Controls] Added QQuickAttachedPropertyPropagator, which
provides a way to propagate attached properties from parent objects
to children. This is especially useful when creating your own style.

Fixes: QTBUG-63267
Change-Id: I2f1794dc4a9f2be56fad2f5e5f39e2ab845157fa
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

Replace the current license disclaimer in files by
a SPDX-License-Identifier.
Files that have to be modified by hand are modified.
License files are organized under LICENSES directory.

Pick-to: 6.4
Task-number: QTBUG-67283
Change-Id: I63563bbeb6f60f89d2c99660400dca7fab78a294
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

Including moc files directly into their classes' TU tends to improve
codegen and enables extended compiler warnings, e.g. about unused
private functions or fields.

Pick-to: 6.3 6.2 5.15
Task-number: QTBUG-102948
Change-Id: Ic31f4d16eb4dd63a5f3d5aa1940e538932709813
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

+ Removed some .constData where it was not needed

Change-Id: Ib52c6ec1a5e691c952a82903dea76d79535c72b7
Reviewed-by: Marc Mutz <marc.mutz@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

Remove usages of outdated LGPL3 header that references LICENSES.LGPLv3
instead of LICENSES.LGPL3.

Change-Id: If7a90ec18331a68491c5a740f131a5e7b3f37df4
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

Make the button lighter in the light and dark themes.

Fixes: QTBUG-91886
Pick-to: 6.2
Change-Id: I0c21eef31e82cf23b729c16ae469e2938d6c490c
Reviewed-by: Oliver Eftevaag <oliver.eftevaag@qt.io>
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

The new qml CMake API places a closer relationship between
the backing target and the plugin target. Both are typically
created together and they share a lot of common details.
Instead of creating them in different parts of the source
tree, they are now specified together. The src/imports
area has effectively been absorbed into the other
corresponding subdirectories below src with this change.

Task-number: QTBUG-91621
Change-Id: I9bd32e9eb78c198ccc9db04e2829303cac323502
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>