Add support for messages.json format used to localize Chrome extensions.

grit/node/empty.py

 #!/usr/bin/env python
 # 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.
 
 '''Container nodes that don't have any logic.
 '''
 
 
 from grit.node import base
@@ skipping 31 matching lines @@
     '''Return the stringtable itemformatter if an RC is being formatted.'''
     if t in ['rc_all', 'rc_translateable', 'rc_nontranslateable']:
       from grit.format import rc  # avoid circular dep by importing here
       return rc.StringTable()
     elif t == 'c_format':
       from grit.format import c_format
       return c_format.StringTable()
     elif t == 'js_map_format':
       from grit.format import js_map_format
       return js_map_format.StringTable()
+    elif t == 'chrome_messages_json':
+      from grit.format import chrome_messages_json
+      return chrome_messages_json.StringTable()
     elif t == 'android':
       from grit.format import android_xml
       return android_xml.ResourcesElement()
 
 
 class StructuresNode(GroupingNode):
   '''The <structures> element.'''
   def _IsValidChild(self, child):
     return isinstance(child, (structure.StructureNode, misc.SplicingNode))
 
 
 class TranslationsNode(base.Node):
   '''The <translations> element.'''
   def _IsValidChild(self, child):
     return isinstance(child, (io.FileNode, misc.SplicingNode))
 
 
 class OutputsNode(base.Node):
   '''The <outputs> element.'''
   def _IsValidChild(self, child):
     return isinstance(child, (io.OutputNode, misc.SplicingNode))
 
 
 class IdentifiersNode(GroupingNode):
   '''The <identifiers> element.'''
   def _IsValidChild(self, child):
     from grit.node import misc
     return isinstance(child, misc.IdentifierNode)