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

grit/format/js_map_format_unittest.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.
 
 """Unittest for js_map_format.py.
 """
 
 import os
 import sys
@@ skipping 21 matching lines @@
       </message>
       <message name="IDS_PLACEHOLDERS">
               <ph name="ERROR_COUNT">%1$d<ex>1</ex></ph> error, <ph name="WARNING_COUNT">%2$d<ex>1</ex></ph> warning
       </message>
       <message name="IDS_STARTS_WITH_SPACE">
               ''' (<ph name="COUNT">%d<ex>2</ex></ph>)
       </message>
       <message name="IDS_DOUBLE_QUOTES">
               A "double quoted" message.
       </message>
+      <message name="IDS_BACKSLASH">
+              \\
+      </message>
     </messages>
     """
     root = grd_reader.Parse(StringIO.StringIO(grd_text.encode('utf-8')),
                             flexible_root=True)
     util.FixRootForUnittest(root)
 
     buf = StringIO.StringIO()
     build.RcBuilder.ProcessNode(root, DummyOutput('js_map_format', 'en'), buf)
     output = buf.getvalue()
     test = u"""
 localizedStrings["Simple message."] = "Simple message.";
 localizedStrings["element\u2019s \u201c%s\u201d attribute"] = "element\u2019s \u201c%s\u201d attribute";
 localizedStrings["%d error, %d warning"] = "%1$d error, %2$d warning";
 localizedStrings[" (%d)"] = " (%d)";
 localizedStrings["A \\\"double quoted\\\" message."] = "A \\\"double quoted\\\" message.";
+localizedStrings["\\\\"] = "\\\\";
 """
     self.failUnless(output.strip() == test.strip())
 
   def testTranslations(self):
     root = grd_reader.Parse(StringIO.StringIO("""
     <messages>
         <message name="ID_HELLO">Hello!</message>
         <message name="ID_HELLO_USER">Hello <ph name="USERNAME">%s<ex>
           Joi</ex></ph></message>
       </messages>
@@ skipping 20 matching lines @@
     return self.type
 
   def GetLanguage(self):
     return self.language
 
   def GetOutputFilename(self):
     return 'hello.gif'
 
 if __name__ == '__main__':
   unittest.main()