iOS: notify application when edit menu is closed

The edit menu will also close if the user taps outside it, not only
when selecting a menu item. But we never caught this case, which left
QMenu to belive that it was still open.

Change-Id: Iae071b4fc5fdc44d7d05b4dd767042907e337957
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@theqtcompany.com>

src/plugins/platforms/ios/qiosmenu.mm

@@ -61,11 +61,23 @@ static NSString *const kSelectorPrefix = @"_qtMenuItem_";
 {
     if (self = [super init]) {
         [self setVisibleMenuItems:visibleMenuItems];
+        [[NSNotificationCenter defaultCenter]
+            addObserver:self
+            selector:@selector(menuClosed)
+            name:UIMenuControllerDidHideMenuNotification object:nil];
     }
 
     return self;
 }
 
+-(void)dealloc
+{
+    [[NSNotificationCenter defaultCenter]
+        removeObserver:self
+        name:UIMenuControllerDidHideMenuNotification object:nil];
+    [super dealloc];
+}
+
 - (void)setVisibleMenuItems:(const QIOSMenuItemList &)visibleMenuItems
 {
     m_visibleMenuItems = visibleMenuItems;
@@ -85,6 +97,11 @@ static NSString *const kSelectorPrefix = @"_qtMenuItem_";
         [[UIMenuController sharedMenuController] setMenuVisible:YES animated:NO];
 }
 
+-(void)menuClosed
+{
+    QIOSMenu::currentMenu()->dismiss();
+}
+
 - (id)targetForAction:(SEL)action withSender:(id)sender
 {
     Q_UNUSED(sender);