Fix bug with using enums as default values in mojom. We were previously

mojo/public/bindings/pylib/generate/mojom_generator.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.
 
 """Code shared by the various language-specific code generators."""
 
 import os
 import mojom
 import mojom_pack
 import re
@@ skipping 35 matching lines @@
   values. Arrays are tokens that look like ('ARRAY', element0, element1...).
   See mojom_parser.py for their representation.
   """
   if not isinstance(token, tuple):
     raise Exception("Expected token type '%s'. Invalid token '%s'." %
         (expected, token))
   if token[0] != expected:
     raise Exception("Expected token type '%s'. Got '%s'." %
         (expected, token[0]))
 
+def ExpressionMapper(expression, mapper):
+  if isinstance(expression, tuple) and expression[0] == 'EXPRESSION':
+    result = []
+    for each in expression[1]:
+      result.extend(ExpressionMapper(each, mapper))
+    return result
+  return [mapper(expression)]
+
 class Generator(object):
   # Pass |output_dir| to emit files to disk. Omit |output_dir| to echo all
   # files to stdout.
   def __init__(self, module, header_dir, output_dir=None):
     self.module = module
     self.header_dir = header_dir
     self.output_dir = output_dir
 
   def GetStructsFromMethods(self):
     result = []
     for interface in self.module.interfaces:
       for method in interface.methods:
         result.append(GetStructFromMethod(interface, method))
     return map(partial(GetStructInfo, False), result)
 
   def GetStructs(self):
     return map(partial(GetStructInfo, True), self.module.structs)
 
   def Write(self, contents, filename):
     if self.output_dir is None:
       print contents
       return
     with open(os.path.join(self.output_dir, filename), "w+") as f:
       f.write(contents)
 
   def GenerateFiles(self):
     raise NotImplementedError("Subclasses must override/implement this method")