Two-part fix: QCocoaMenu::syncMenuItem, when selecting the "old" menu,
if an item was merged, 'applicationMenu' was always selected, but this
is wrong for any item with a role >= CutRole (such an item still can
be "merged", but it's not in the application menu).
QCocoaMenuItem::sync - item can be merged with itself: after item's
role detected, the search for an item to merge with can find exactly
the same item we've just detected the role for (since a data-member is
modified) - try to avoid this.
Task-number: QTBUG-39934
Change-Id: Ibe1df9e92973380652101143067e14922afdfb9e
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
8c538d10da