Menu: Support QQuickWindows embedded in QWidgets

We translate the menu popup window by its transient parent origin
coordinates, but if it's embedded in a QWidget, we would only translate
by the transient parent's origin inside that QWidget. So, in this case.
we translate by the transient parent's origin in the global coordinate
reference system.

Task-number: QTBUG-31659
Change-Id: I09aa64f2d61d227d4fcd6d6e22a25453e1f2dc76
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Mac: respect scrollbar style changes

Task-number: QTBUG-31537
Change-Id: I670730934a48655f65df4f2be44e6ce8fa6bbdf7
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>
SpinBox: omit group separators

Task-number: QTBUG-31839
Change-Id: I90879cbc116f399f07e2ae53e998253f2e81a5e2
Reviewed-by: Caroline Chao <caroline.chao@digia.com>
Keep TextField placeholder text visible when focused

This is useful when the widget is focused by default, and also gives
another opportunity to the user to read the message before typing,
removing the need for workarounds like clicking in another text entry to
bring back the placeholder message.

Same as qtbase commit eeb31ad1 for QLineEdit.

Change-Id: I466dd66490e05503b51e208beefd5366b25fd939
Reviewed-by: Caroline Chao <caroline.chao@digia.com>
TableView: let delegates handle mouse events

Includes auto tests.

Task-number: QTBUG-31206
Change-Id: I683363f70f7e360cc70f84fd460cbde5e70a61af
Reviewed-by: Caroline Chao <caroline.chao@digia.com>
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@digia.com>
Text example: specify the base URL for the TextArea

So the TextArea looks inside its own resource file while
resolving relative urls used in the text.

Change-Id: Id67f3f3cbbd635e8defa04d97602e1e7b293874e
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Make import of QtQuick.Controls.Private consistent

Import QtQuick.Controls when QtQuick.Controls.Private
is imported.

Change-Id: I2c962b7310a74e0905e8cec08ee6563a5d98e9d7
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Merge remote-tracking branch 'origin/stable' into dev

Change-Id: Ic7ea23c491b1938f33a30be6e4e5febd8ae7c380