[IMP] qweb.render: t-esc/t-raw rendered as False or None replaced by empty strings

bzr revid: odo@openerp.com-20140129180600-0c155g520gpvnqqf

openerp/addons/base/ir/ir_qweb.py

@@ -181,6 +181,8 @@ class QWeb(orm.AbstractModel):
         val = self.eval(expr, qwebcontext)
         if isinstance(val, unicode):
             return val.encode("utf8")
+        if val is False or val is None:
+            return ''
         return str(val)
 
     def eval_format(self, expr, qwebcontext):