[vala] Report error on invalid using directives

[Jürg Billeter <juergbi src gnome org>]

commit 9d947dfff41159302f357cd1710f0c0bd4aca6a7
Author: Aaron Andersen <aaron fosslib net>
Date:   Fri Aug 20 18:02:14 2010 +0200

    Report error on invalid using directives
    
    Fixes bug 626103.

 vala/valasymbolresolver.vala |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/vala/valasymbolresolver.vala b/vala/valasymbolresolver.vala
index 6483541..026d6ea 100644
--- a/vala/valasymbolresolver.vala
+++ b/vala/valasymbolresolver.vala
@@ -215,7 +215,7 @@ public class Vala.SymbolResolver : CodeVisitor {
 		var unresolved_symbol = ns.namespace_symbol as UnresolvedSymbol;
 		if (unresolved_symbol != null) {
 			ns.namespace_symbol = resolve_symbol (unresolved_symbol);
-			if (ns.namespace_symbol == null) {
+			if (!(ns.namespace_symbol is Namespace)) {
 				ns.error = true;
 				Report.error (ns.source_reference, "The namespace name `%s' could not be found".printf (unresolved_symbol.to_string ()));
 				return;