Cocoa: Disable “Hide” menu item on open popups

Follow native behavior and disable ⌘H and the “Hide”
menu item if there are any open popup windows.

Task-number: QTBUG-58727
Change-Id: Iad38cc5cce29e0081613417c53b154ae0f05857e
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>

src/plugins/platforms/cocoa/qcocoamenuloader.mm

@@ -43,6 +43,7 @@
 #include "qcocoahelpers.h"
 #include "qcocoamenubar.h"
 #include "qcocoamenuitem.h"
+#include "qcocoaintegration.h"
 
 #include <QtCore/private/qcore_mac_p.h>
 #include <QtCore/private/qthread_p.h>
@@ -343,10 +344,13 @@
 
 - (BOOL)validateMenuItem:(NSMenuItem*)menuItem
 {
-    if ([menuItem action] == @selector(hide:)
-        || [menuItem action] == @selector(hideOtherApplications:)
+    if ([menuItem action] == @selector(hideOtherApplications:)
         || [menuItem action] == @selector(unhideAllApplications:)) {
         return [NSApp validateMenuItem:menuItem];
+    } else if ([menuItem action] == @selector(hide:)) {
+        if (QCocoaIntegration::instance()->activePopupWindow())
+            return NO;
+        return [NSApp validateMenuItem:menuItem];
     } else if ([menuItem tag]) {
         QCocoaMenuItem *cocoaItem = reinterpret_cast<QCocoaMenuItem *>([menuItem tag]);
         return cocoaItem->isEnabled();