cocoa: properly unhide Dock when quitting during System fs animation

when quitting mpv during the System fullscreen animation cocoa can't
reset some flags properly and won't reset the Dock hiding behaviour
to it's previous state.

Fixes #4400

video/out/cocoa/window.m

@@ -159,16 +159,28 @@
     [self.adapter windowDidExitFullScreen:notification];
 }
 
+- (void)windowWillEnterFullScreen:(NSNotification *)notification
+{
+    [self.adapter windowWillEnterFullScreen:notification];
+}
+
+- (void)windowWillExitFullScreen:(NSNotification *)notification
+{
+    [self.adapter windowWillExitFullScreen:notification];
+}
+
 - (void)windowDidFailToEnterFullScreen:(NSWindow *)window
 {
     _is_animating = 0;
     [self setToWindow];
+    [self.adapter windowDidFailToEnterFullScreen:window];
 }
 
 - (void)windowDidFailToExitFullScreen:(NSWindow *)window
 {
     _is_animating = 0;
     [self setToFullScreen];
+    [self.adapter windowDidFailToExitFullScreen:window];
 }
 
 - (void)windowDidChangeBackingProperties:(NSNotification *)notification

video/out/cocoa_common.m

@@ -93,6 +93,10 @@ struct vo_cocoa_state {
     uint32_t old_dwidth;
     uint32_t old_dheight;
 
+    pthread_mutex_t anim_lock;
+    pthread_cond_t anim_wakeup;
+    bool is_animating;
+
     CVDisplayLinkRef link;
     pthread_mutex_t sync_lock;
     pthread_cond_t sync_wakeup;
@@ -294,6 +298,23 @@ static void vo_cocoa_update_screen_info(struct vo *vo)
     s->display_id = [[sinfo objectForKey:@"NSScreenNumber"] longValue];
 }
 
+static void vo_cocoa_anim_lock(struct vo *vo)
+{
+    struct vo_cocoa_state *s = vo->cocoa;
+    pthread_mutex_lock(&s->anim_lock);
+    s->is_animating = true;
+    pthread_mutex_unlock(&s->anim_lock);
+}
+
+static void vo_cocoa_anim_unlock(struct vo *vo)
+{
+    struct vo_cocoa_state *s = vo->cocoa;
+    pthread_mutex_lock(&s->anim_lock);
+    s->is_animating = false;
+    pthread_cond_signal(&s->anim_wakeup);
+    pthread_mutex_unlock(&s->anim_lock);
+}
+
 static void vo_cocoa_signal_swap(struct vo_cocoa_state *s)
 {
     pthread_mutex_lock(&s->sync_lock);
@@ -363,6 +384,8 @@ void vo_cocoa_init(struct vo *vo)
     pthread_cond_init(&s->wakeup, NULL);
     pthread_mutex_init(&s->sync_lock, NULL);
     pthread_cond_init(&s->sync_wakeup, NULL);
+    pthread_mutex_init(&s->anim_lock, NULL);
+    pthread_cond_init(&s->anim_wakeup, NULL);
     vo->cocoa = s;
     vo_cocoa_update_screen_info(vo);
     vo_cocoa_init_displaylink(vo);
@@ -407,6 +430,11 @@ void vo_cocoa_uninit(struct vo *vo)
     pthread_cond_signal(&s->wakeup);
     pthread_mutex_unlock(&s->lock);
 
+    pthread_mutex_lock(&s->anim_lock);
+    while(s->is_animating)
+        pthread_cond_wait(&s->anim_wakeup, &s->anim_lock);
+    pthread_mutex_unlock(&s->anim_lock);
+
     // close window beforehand to prevent undefined behavior when in fullscreen
     // that resets the desktop to space 1
     run_on_main_thread(vo, ^{
@@ -436,6 +464,8 @@ void vo_cocoa_uninit(struct vo *vo)
         [s->view removeFromSuperview];
         [s->view release];
 
+        pthread_cond_destroy(&s->anim_wakeup);
+        pthread_mutex_destroy(&s->anim_lock);
         pthread_cond_destroy(&s->sync_wakeup);
         pthread_mutex_destroy(&s->sync_lock);
         pthread_cond_destroy(&s->wakeup);
@@ -1014,6 +1044,7 @@ int vo_cocoa_control(struct vo *vo, int *events, int request, void *arg)
     struct vo_cocoa_state *s = self.vout->cocoa;
     s->fullscreen = 1;
     s->pending_events |= VO_EVENT_FULLSCREEN_STATE;
+    vo_cocoa_anim_unlock(self.vout);
 }
 
 - (void)windowDidExitFullScreen:(NSNotification *)notification
@@ -1021,6 +1052,27 @@ int vo_cocoa_control(struct vo *vo, int *events, int request, void *arg)
     struct vo_cocoa_state *s = self.vout->cocoa;
     s->fullscreen = 0;
     s->pending_events |= VO_EVENT_FULLSCREEN_STATE;
+    vo_cocoa_anim_unlock(self.vout);
+}
+
+- (void)windowWillEnterFullScreen:(NSNotification *)notification
+{
+    vo_cocoa_anim_lock(self.vout);
+}
+
+- (void)windowWillExitFullScreen:(NSNotification *)notification
+{
+    vo_cocoa_anim_lock(self.vout);
+}
+
+- (void)windowDidFailToEnterFullScreen:(NSWindow *)window
+{
+    vo_cocoa_anim_unlock(self.vout);
+}
+
+- (void)windowDidFailToExitFullScreen:(NSWindow *)window
+{
+    vo_cocoa_anim_unlock(self.vout);
 }
 
 - (void)windowWillStartLiveResize:(NSNotification *)notification