Docserver: Attach intro metadata to the template itself, not to an object which

chrome/common/extensions/docs/server2/render_servlet.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 fnmatch import fnmatch
 import logging
 import mimetypes
 import posixpath
 import traceback
 from urlparse import urlsplit
 
 from data_source_registry import CreateDataSources
+from environment import IsPreviewServer
 from file_system import FileNotFoundError
 from redirector import Redirector
 from servlet import Servlet, Response
 from third_party.handlebar import Handlebar
 
 
 def _MakeHeaders(content_type):
   return {
     'X-Frame-Options': 'sameorigin',
     'Content-Type': content_type,
@@ skipping 17 matching lines @@
     ''' Render the page for a request.
     '''
     # TODO(kalman): a consistent path syntax (even a Path class?) so that we
     # can stop being so conservative with stripping and adding back the '/'s.
     path = self._request.path.lstrip('/')
     server_instance = self._delegate.CreateServerInstance()
 
     try:
       return self._GetSuccessResponse(path, server_instance)
     except FileNotFoundError:
+      if IsPreviewServer():
+        logging.error(traceback.format_exc())
       # Maybe it didn't find the file because its canonical location is
       # somewhere else; this is distinct from "redirects", which are typically
       # explicit. This is implicit.
       canonical_result = server_instance.path_canonicalizer.Canonicalize(path)
       redirect = canonical_result.path.lstrip('/')
       if path != redirect:
         return Response.Redirect('/' + redirect,
                                  permanent=canonical_result.permanent)
 
       # Not found for reals. Find the closest 404.html file and serve that;
@@ skipping 37 matching lines @@
     content = content_and_type.content
     if isinstance(content, Handlebar):
       content = server_instance.template_renderer.Render(content, self._request)
 
     content_type = content_and_type.content_type
     if isinstance(content, unicode):
       content = content.encode('utf-8')
       content_type += '; charset=utf-8'
 
     return Response.Ok(content, headers=_MakeHeaders(content_type))