Merge lp:~gala-dev/gala/get-window-actors-crash into lp:gala

[Tom Beckmann]

Some code to hopefully prevent the meta_get_window_actors crash.

[Rico Tzschichholz (ricotz)]

review: Approve

=== modified file 'src/Widgets/WindowSwitcher.vala'
--- src/Widgets/WindowSwitcher.vala	2013-04-28 09:30:41 +0000
+++ src/Widgets/WindowSwitcher.vala	2013-05-11 13:14:27 +0000
@@ -182,7 +182,11 @@
 				window_clones.clear ();
 				
 				//need to go through all the windows because of hidden dialogs
-				foreach (var window in Meta.Compositor.get_window_actors (screen)) {
+				unowned List<Meta.WindowActor>? window_actors = Meta.Compositor.get_window_actors (screen);
+				warn_if_fail (window_actors != null);
+				if (window_actors == null)
+					return;
+				foreach (var window in window_actors) {
 					if (window.get_workspace () == workspace.index ())
 						window.show ();
 				}

=== modified file 'src/Widgets/WorkspaceThumb.vala'
--- src/Widgets/WorkspaceThumb.vala	2013-03-29 17:45:46 +0000
+++ src/Widgets/WorkspaceThumb.vala	2013-05-11 13:14:27 +0000
@@ -332,8 +332,10 @@
 		void update_windows ()
 		{
 			windows.remove_all_children ();
+			unowned List<WindowActor>? window_actors = Compositor.get_window_actors (screen);
+			warn_if_fail (window_actors != null);
 			
-			if (workspace == null)
+			if (workspace == null || window_actors == null)
 				return;
 			
 			int swidth, sheight;
@@ -341,7 +343,7 @@
 			
 			// add window thumbnails
 			var aspect = windows.width / swidth;
-			foreach (var window in Compositor.get_window_actors (screen)) {
+			foreach (var window in window_actors) {
 				if (window == null)
 					continue;
 				var meta_window = window.get_meta_window ();