Show the path when a json file fails to parse.

chrome/common/extensions/docs/server2/schema_util.py

 # Copyright 2013 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.
 
 from collections import defaultdict, Mapping
+import traceback
 
 from third_party.json_schema_compiler import json_parse, idl_schema, idl_parser
 
 
 def RemoveNoDocs(item):
   '''Removes nodes that should not be rendered from an API schema.
   '''
   if json_parse.IsDict(item):
     if item.get('nodoc', False):
       return True
@@ skipping 88 matching lines @@
     if is_idl:
       DetectInlineableTypes(schema)
     InlineDocs(schema)
     return schema
 
   if path.endswith('.idl'):
     idl = idl_schema.IDLSchema(idl_parser.IDLParser().ParseData(file_data))
     # Wrap the result in a list so that it behaves like JSON API data.
     return [trim_and_inline(idl.process()[0], is_idl=True)]
 
-  schemas = json_parse.Parse(file_data)
+  try:
+    schemas = json_parse.Parse(file_data)
+  except:
+    raise ValueError('Cannot parse "%s" as JSON:\n%s' %
+                     (path, traceback.format_exc()))
   for schema in schemas:
     # Schemas could consist of one API schema (data for a specific API file)
     # or multiple (data from extension_api.json).
     trim_and_inline(schema)
   return schemas