[vala] Fix critical when using binary expression in a generics context

[Luca Bruno <lucabru src gnome org>]

commit ef9cdf86352f5d7d50b34eec6a602d7c6e13ae0a
Author: Luca Bruno <luca bruno immobiliare it>
Date:   Fri Aug 29 16:43:32 2014 +0200

    Fix critical when using binary expression in a generics context
    
    Fixes bug 735117

 vala/valabinaryexpression.vala |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/vala/valabinaryexpression.vala b/vala/valabinaryexpression.vala
index 98b2e5e..8ccddba 100644
--- a/vala/valabinaryexpression.vala
+++ b/vala/valabinaryexpression.vala
@@ -186,6 +186,7 @@ public class Vala.BinaryExpression : Expression {
 
                        var ma = new MemberAccess.simple (local.name, source_reference);
                        ma.target_type = target_type;
+                       ma.formal_target_type = formal_target_type;
                        ma.check (context);
 
                        parent_node.replace_expression (this, ma);