QCocoaDrag: reset the stored NSView when it gets destroyed

QCocoaDrag stores the last NSView that received an input event, which
becomes a dangling pointer when the NSView gets destroyed. Inform the
QCocoaDrag when NSView's destructor runs, so that it can reset the
pointer (and reset the NSEvent pointer as well) when the destroyed
NSView is the stored one.

With this change alone we'd end up triggering the Q_ASSERT later on in
QCocoaDrag::drag, as m_lastEvent is now nil so the NSWindow will be nil
as well. QCocoaDrag::drag cannot do anything useful if m_lastEvent is
nil, so exit early.

Pick-to: 6.8 6.5
Fixes: QTBUG-116554
Change-Id: I5949d728d05adcf3d4a32c91f7e181393bef0422
Reviewed-by: Tor Arne Vestbø <[email protected]>

0 files changed, 0 insertions, 0 deletions