[IMP]Give a proper message When a validate or import is refused due to a problem.

bzr revid: vba@tinyerp.com-20121030091231-ty2edtpcjyaxqzzx

addons/base_import/models.py

@@ -316,9 +316,17 @@ class ir_import(orm.TransientModel):
             }]
 
         _logger.info('importing %d rows...', len(data))
-        import_result = self.pool[record.res_model].load(
-            cr, uid, import_fields, data, context=context)
-        _logger.info('done')
+        try:
+            import_result = self.pool[record.res_model].load(
+                cr, uid, import_fields, data, context=context)
+            _logger.info('done')
+        except Exception, e:
+            _logger.info(e)
+            return [{
+                'type': 'error',
+                'message': unicode('No data have been imported.'),
+                'record': False,
+            }]
 
         # If transaction aborted, RELEASE SAVEPOINT is going to raise
         # an InternalError (ROLLBACK should work, maybe). Ignore that.