QRegularExpression: add method for extracting the capturing group names

It may be useful to know which named capturing groups are defined
in an regular expression, and for each of them, what's the
corresponding index. This commit adds the needed method
to QRegularExpression.

Note that extracting the information doesn't happen while holding
the mutex in the private -- pcre_fullinfo just reads information
from the compiled pattern, so that's thread-safe.

Task-number: QTBUG-29079
Change-Id: I50c00ee860f06427c2e6ea10417d5c0733cc8303
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Add qDegreesToRadians and qRadiansToDegrees math functions

Change-Id: I6e9fd76f2d2860f46531a72349b46193b8eeaaa7
Reviewed-by: Samuel Rødal <samuel.rodal@digia.com>
Manual test for QFontDialog

Change-Id: I2bcdd30990e88af45c8d4b2756fcdd48fc2a47d7
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Add enablers for Android port in QPlatformMenu

We need a couple of functions here for the Android support.

Change-Id: I50e27277d7e838e277d616dbd3af9be817fb7197
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>
qsql ibase: remove duplicate class definition

Follow-up to 1580f558472e2c37936fe817fc546a79a8b0a9a5

Task-number: QTBUG-29455
Change-Id: Id254a166ac901fb0cc0ba81db4bf1051a2acb53f
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Add QT_{BEGIN,END}_HEADER definition back

This commit partially reverts 07e3bcdc106ac42703ae0fb88b6cac2d2bfdd072
The empty macro defition was not supposed to be removed yet.

Change-Id: Ie83b2adbe2328b83c70a70274a401e1e6c74498f
Reviewed-by: David Faure (KDE) <faure@kde.org>
Allow overriding subElementRect in QProxyStyle for ItemViewItem

proxy() should be used instead of direct calls to QCommonStyle methods
to allow overriding behavior in QProxyStyle, while keeping fallback
to default behavior.

Change-Id: I338e6b65f4c0ee77c55f03c412f59877fad42b79
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@digia.com>