gstwaylandsink: Add support for the "render-rectangle" property

We already implement the `set_render_rectangle` videooverlay interface,
thus install the videooverlay property accordingly.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2479>

subprojects/gst-plugins-bad/docs/plugins/gst_plugins_cache.json

@@ -230406,6 +230406,17 @@
                         "readable": true,
                         "type": "gboolean",
                         "writable": true
+                    },
+                    "render-rectangle": {
+                        "blurb": "The render rectangle ('<x, y, width, height>')",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "mutable": "null",
+                        "readable": false,
+                        "type": "GstValueArray",
+                        "writable": true
                     }
                 },
                 "rank": "marginal"

subprojects/gst-plugins-bad/ext/wayland/gstwaylandsink.c

@@ -59,7 +59,8 @@ enum
 {
   PROP_0,
   PROP_DISPLAY,
-  PROP_FULLSCREEN
+  PROP_FULLSCREEN,
+  PROP_LAST
 };
 
 GST_DEBUG_CATEGORY (gstwayland_debug);
@@ -160,6 +161,16 @@ gst_wayland_sink_class_init (GstWaylandSinkClass * klass)
       g_param_spec_boolean ("fullscreen", "Fullscreen",
           "Whether the surface should be made fullscreen ", FALSE,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ /**
+  * waylandsink:render-rectangle:
+  *
+  * This helper installs the "render-rectangle" property into the
+  * class.
+  *
+  * Since: 1.22
+  */
+  gst_video_overlay_install_properties (gobject_class, PROP_LAST);
 }
 
 static void