cocoa: fix key equivalent dispatching

Prior to this commit we had a list of key modifiers and checked against that.
Actually, the Cocoa framework has a built in way to do it and it involves
calling performKeyEquivalent: on the menu instance.

Fixes #946

cc @mpv-player/stable: this should apply with no conflicts

osdep/macosx_application.m

@@ -86,7 +86,12 @@ Application *mpv_shared_app(void)
 
         [NSEvent addLocalMonitorForEventsMatchingMask:NSKeyDownMask|NSKeyUpMask
                                               handler:^(NSEvent *event) {
+            BOOL equivalent = [[NSApp mainMenu] performKeyEquivalent:event];
+            if (equivalent) {
+                return (NSEvent *)nil;
+            } else {
                 return [self.eventsResponder handleKey:event];
+            }
         }];
 
         NSAppleEventManager *em = [NSAppleEventManager sharedAppleEventManager];

osdep/macosx_events.m

@@ -233,21 +233,6 @@ void cocoa_put_key_with_modifiers(int keycode, int modifiers)
     });
 }
 
-- (NSArray *) keyEquivalents
-{
-    return @[@"h", @"q", @"Q", @"0", @"1", @"2"];
-}
-
-- (BOOL)isAppKeyEquivalent:(NSString *)eq withEvent:(NSEvent *)event
-{
-    if ([event modifierFlags] & NSCommandKeyMask)
-        for(NSString *c in [self keyEquivalents])
-            if ([eq isEqualToString:c])
-                return YES;
-
-    return NO;
-}
-
 - (BOOL)handleMediaKey:(NSEvent *)event
 {
     NSDictionary *keymapd = @{
@@ -349,13 +334,8 @@ void cocoa_put_key_with_modifiers(int keycode, int modifiers)
 
     int key = convert_key([event keyCode], *[chars UTF8String]);
 
-    if (key > -1) {
-        if ([self isAppKeyEquivalent:chars withEvent:event])
-            // propagate the event in case this is a menu key equivalent
-            return event;
-
+    if (key > -1)
         [self handleMPKey:key withMask:[self keyModifierMask:event]];
-    }
 
     return nil;
 }