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>

The Item's palette property and Control's font property returns the
resolved value; its resolveMask is inherited from parent object, when
the return value is used in the qml. For example:

ApplicationWindow {
    id: window
    palette { window: "blue"; windowText: "blue" }

    Control {
        id: control
    }

    Button {
        onClicked: {
            control.palette.window = "red"
            window.palette.windowText = "red"
            console.log(control.palette.windowText)
        }
    }
}

In Button.onClicked, `control.palette` is the `resolvedPalette`
of Control, it's resolveMask is not 0. Next, the new value is assigned
to the control, then the control's "requestedPalette" will change to the
new value, and it's resolveMask also is not 0. Next,
`window.palette.windowText = "red"` changes the `windowText` palette for
the window; QQuickPaletteColorProvider::inheritPalette() will be called.
Because the resolveMask of `requestedPalette` is equal to the new
palette, the control will not inherit any colors from its parent. So
`console.log(control.palette.windowText)` was printing `qml: #0000ff`,
but the right result is `qml: #ff0000`.

When PaletteProvider is missing the inherited struct, fallbackPalette is
now used as parentPalette.

[ChangeLog][Controls] Controls now inherit palette and font from parents.

Done-With: Volker Hilsheimer <volker.hilsheimer@qt.io>
Done-With: yeshanshan <yeshanshan@uniontech.com>
Done-With: Shawn Rutledge <shawn.rutledge@qt.io>
Pick-to: 6.4
Fixes: QTBUG-101480
Change-Id: Ibe400f647512331352bf34dee42f908fb7a8d914
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Oliver Eftevaag <oliver.eftevaag@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>

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>

Font overriding should be a style-specific behavior. For instance, macos
style cannot use a different font size than the default. Therefore, this
patch moves the font overriding over to the macos style.

This prevented font size to be inherited from the parent control
Fixes autotests Popup::test_font() and ComboBox::test_font() on Windows
style.

Task-number: QTBUG-95679
Pick-to: 6.2
Change-Id: Ic24de04a517a8a8710f916e70117729c41c1534e
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@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>