Keep web fontdata alive as long as CG uses it

With OS X 10.9 font decoding appears to happen lazily, this means we
have
to ensure the data we provide CG is kept alive until it dereferences it
itself.

Task-number: QTBUG-34332
Change-Id: I8fc38fafba746b062c4ad16314b0a410fd0b668d
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>
Different native Cocoa menu fixes.

- Fix location of NSMenu when no NSView is given.
- Fix shortcut when given in text with tab.

Change-Id: Iec21cf3d12084db1e70c1a8779d5482c78285796
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>