Extensions Docs Server: Uniform handling of file not found errors

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

 # Copyright (c) 2012 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.
 
 import logging
 
 from docs_server_utils import FormatKey
+from file_system import FileNotFoundError
 from third_party.handlebar import Handlebar
 
 EXTENSIONS_URL = '/chrome/extensions'
 
 def _MakeBranchDict(branch):
   return {
     'showWarning': branch != 'stable',
     'branches': [
       { 'name': 'Stable', 'path': 'stable' },
       { 'name': 'Dev',    'path': 'dev' },
@@ skipping 100 matching lines @@
   def __getitem__(self, key):
     return self.get(key)
 
   def get(self, key):
     return self.GetTemplate(self._private_template_path, key)
 
   def GetTemplate(self, base_path, template_name):
     real_path = FormatKey(template_name)
     try:
       return self._cache.GetFromFile(base_path + '/' + real_path)
-    except Exception as e:
+    except FileNotFoundError as e:
       logging.error(e)
       return None