KDE4: Drop Qt 4.9 support

I don't think there will ever be any 4.9 release, so drop all the
unused code.

Change-Id: I4b72de96e6064240582cd83d4e45547096a2efb0
KDE4: sleep in yield for native file picker

As it seems to be the only way to poll the clipboard, reintroduce

 m_pApplication->clipboard()->setProperty(
    "useEventLoopWhenWaiting", true );

To prevent crashes, disable event processing in the Qt thread while
the dialog is open.

Instead this applies the same workaround as the Windows backend to
sleep a ms, which keeps the FP dialogs more usable, but feels like
a horrible workaround.

This is still slower then running processEvent in Yield but still
much better then the current situation.

Change-Id: I10c422f1c0d7448d4a7ad28e57a32ed2cb42f48f
KDE4: Report correct check and radio item sizes

Use the correct sizs from the current style.

Change-Id: I7e163bdc8d467baf2d6e3d0d2bc3e1da7558cf42
fdo#45935: try hard to paint a frame for menus

Current Oxygen theme doesn't draw frames for menus, but uses shaped
and "colored" background images. This workaround paints the window
and menu frame for menus. Any frame seems to be better then no frame
at all.

Change-Id: I4d553ea58cac2729826f8395cb2597fa200187b6
KDE4: evaluate frameWidth in the Qt thread

When opening a document via Java UNO without a running LO instance, one
gets the following Qt error messages:

CE>  QObject: Cannot create children for a parent that is in a different thread.
CE>  (Parent is Oxygen::WidgetStateEngine(0x8deb878), parent's thread is QThread(0x8d6cf70), current thread is QThread(0xa8fa7fc8)
CE>  QObject::installEventFilter(): Cannot filter events for objects in a different thread.
CE>  QObject::installEventFilter(): Cannot filter events for objects in a different thread.
CE>  QObject::installEventFilter(): Cannot filter events for objects in a different thread.

This happens, because the Java UNO call is processed in the first /
Qt thread while document loading happens in a second thread.

Document loading actually just calls getNativeControlRegion, which
should not involve any drawing. But the KDE4 backend does some style
processing to get the correct frame width (QWidget::ensurePolished(),
which uses GUI based events and need to be processed in the Qt
thread.

Change-Id: I344d5089d958963c48a9a8a84bfa9fe8f092b75a