skins2: fix art display misfunctioning in latest git vlc

Art display used to rely on an event issued by vlc core which has been renamed into "activity" lately. The issue was that it seems no longer fired when a new
 input is launched.

modules/gui/skins2/src/vlcproc.cpp

@@ -490,6 +490,28 @@ void VlcProc::on_intf_event_changed( vlc_object_t* p_obj, vlc_value_t newVal )
 
         getIntf()->p_sys->p_input = pInput;
         vlc_object_hold( pInput );
+
+        input_item_t *p_item = input_GetItem( pInput );
+        if( p_item )
+        {
+            // Update short name
+            char *psz_name = input_item_GetName( p_item );
+            SET_TEXT( m_cVarStreamName, UString( getIntf(), psz_name ) );
+            free( psz_name );
+
+            // Update local path (if possible) or full uri
+            char *psz_uri = input_item_GetURI( p_item );
+            char *psz_path = make_path( psz_uri );
+            char *psz_save = psz_path ? psz_path : psz_uri;
+            SET_TEXT( m_cVarStreamURI, UString( getIntf(), psz_save ) );
+            free( psz_path );
+            free( psz_uri );
+
+            // Update art uri
+            char *psz_art = input_item_GetArtURL( p_item );
+            SET_STRING( m_cVarStreamArt, string( psz_art ? psz_art : "" ) );
+            free( psz_art );
+        }
     }
 
     switch( newVal.i_int )