Update //third_party/protobuf to version 3.

third_party/protobuf/python/google/protobuf/pyext/cpp_message.py

Index: third_party/protobuf/python/google/protobuf/pyext/cpp_message.py
diff --git a/third_party/protobuf/python/google/protobuf/internal/message_cpp_test.py b/third_party/protobuf/python/google/protobuf/pyext/cpp_message.py
similarity index 56%
copy from third_party/protobuf/python/google/protobuf/internal/message_cpp_test.py
copy to third_party/protobuf/python/google/protobuf/pyext/cpp_message.py
index 0d84b3207bdd0a5f5b7202e9ad67d6cfcf55e0d3..b215211ee581f2bfa4fa8d06cf3ca3fc27941f56 100644
--- a/third_party/protobuf/python/google/protobuf/internal/message_cpp_test.py
+++ b/third_party/protobuf/python/google/protobuf/pyext/cpp_message.py
@@ -1,8 +1,6 @@
-#! /usr/bin/python
-#
 # Protocol Buffers - Google's data interchange format
 # Copyright 2008 Google Inc.  All rights reserved.
-# http://code.google.com/p/protobuf/
+# https://developers.google.com/protocol-buffers/
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
@@ -30,16 +28,38 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-"""Tests for google.protobuf.internal.message_cpp."""
+"""Protocol message implementation hooks for C++ implementation.
+
+Contains helper functions used to create protocol message classes from
+Descriptor objects at runtime backed by the protocol buffer C++ API.
+"""
+
+__author__ = 'tibell@google.com (Johan Tibell)'
+
+from google.protobuf.pyext import _message
+
+
+class GeneratedProtocolMessageType(_message.MessageMeta):
 
-__author__ = 'shahms@google.com (Shahms King)'
+  """Metaclass for protocol message classes created at runtime from Descriptors.
 
-import os
-os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'cpp'
+  The protocol compiler currently uses this metaclass to create protocol
+  message classes at runtime.  Clients can also manually create their own
+  classes at runtime, as in this example:
 
-import unittest
-from google.protobuf.internal.message_test import *
+  mydescriptor = Descriptor(.....)
+  class MyProtoClass(Message):
+    __metaclass__ = GeneratedProtocolMessageType
+    DESCRIPTOR = mydescriptor
+  myproto_instance = MyProtoClass()
+  myproto.foo_field = 23
+  ...
 
+  The above example will not work for nested types. If you wish to include them,
+  use reflection.MakeClass() instead of manually instantiating the class in
+  order to create the appropriate class structure.
+  """
 
-if __name__ == '__main__':
-  unittest.main()
+  # Must be consistent with the protocol-compiler code in
+  # proto2/compiler/internal/generator.*.
+  _DESCRIPTOR_KEY = 'DESCRIPTOR'