macos: Set activation policy in osxvideosink and glimagesink

Upon creating a window, glimagesink and osxvideosink now set the policy to
NSApplicationActivationPolicyRegular, which lets us show an icon in the Dock
for convenience and appear in the top menu bar like other apps.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4573>

subprojects/gst-plugins-base/gst-libs/gst/gl/cocoa/gstglwindow_cocoa.m

@@ -236,6 +236,8 @@ gst_gl_window_cocoa_create_window (GstGLWindowCocoa *window_cocoa)
     gst_gl_window_cocoa_set_window_handle (window,
         (guintptr) priv->external_view);
 
+  [NSApp setActivationPolicy:NSApplicationActivationPolicyRegular];
+
   return TRUE;
 }
 

subprojects/gst-plugins-good/sys/osxvideo/osxvideosink.m

@@ -84,7 +84,6 @@ static void
 gst_osx_video_sink_call_from_main_thread(GstOSXVideoSink *osxvideosink,
     NSObject * object, SEL function, NSObject *data, BOOL waitUntilDone)
 {
-
   NSThread *thread;
   NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
 
@@ -148,6 +147,10 @@ gst_osx_video_sink_osxwindow_create (GstOSXVideoSink * osxvideosink, gint width,
       @selector(createInternalWindow), nil, YES);
     GST_INFO_OBJECT (osxvideosink, "No superview, creating an internal window.");
   }
+
+  gst_osx_video_sink_call_from_main_thread (osxvideosink, osxvideosink->osxvideosinkobject,
+    @selector(setActivationPolicy), nil, YES);
+
   [osxwindow->gstview setNavigation: GST_NAVIGATION(osxvideosink)];
   [osxvideosink->osxwindow->gstview setKeepAspectRatio: osxvideosink->keep_par];
 
@@ -659,6 +662,11 @@ gst_osx_video_sink_get_type (void)
 
 }
 
+- (void) setActivationPolicy
+{
+  [NSApp setActivationPolicy: NSApplicationActivationPolicyRegular];
+}
+
 - (void) setView: (NSView*)view
 {
   NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
@@ -814,7 +822,6 @@ no_texture_buffer:
 static gboolean
 plugin_init (GstPlugin * plugin)
 {
-
   if (!gst_element_register (plugin, "osxvideosink",
           GST_RANK_MARGINAL, GST_TYPE_OSX_VIDEO_SINK))
     return FALSE;