Print a grit debugging hint to stdout when a parse exception occurs

tools/grit/grit/grd_reader.py

Index: tools/grit/grit/grd_reader.py
diff --git a/tools/grit/grit/grd_reader.py b/tools/grit/grit/grd_reader.py
index d4fe0f7744e0eb5ae4ed73542435637637189076..82d06d9d8224cc53c137e91b5e26581f6024a8c8 100644
--- a/tools/grit/grit/grd_reader.py
+++ b/tools/grit/grit/grd_reader.py
@@ -1,5 +1,5 @@
 #!/usr/bin/python2.4
-# Copyright (c) 2010 The Chromium Authors. All rights reserved.
+# Copyright (c) 2011 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
@@ -134,6 +134,8 @@ def Parse(filename_or_stream, dir=None, flexible_root=False,
     assert stop_after
     pass
   except:
+    if not debug:
+      print "parse exception: run GRIT with the -x flag to debug .grd problems"
     raise
 
   if not flexible_root or hasattr(handler.root, 'SetOwnDir'):