Update //third_party/protobuf to version 3.

third_party/protobuf/src/google/protobuf/generated_enum_util.h

Index: third_party/protobuf/src/google/protobuf/generated_enum_util.h
diff --git a/third_party/protobuf/src/google/protobuf/io/zero_copy_stream.cc b/third_party/protobuf/src/google/protobuf/generated_enum_util.h
similarity index 80%
copy from third_party/protobuf/src/google/protobuf/io/zero_copy_stream.cc
copy to third_party/protobuf/src/google/protobuf/generated_enum_util.h
index dad6ff14468d031f16baafb2f1ca567961251c43..e4242055e991a2f581669c2198ffc909794da9ac 100644
--- a/third_party/protobuf/src/google/protobuf/io/zero_copy_stream.cc
+++ b/third_party/protobuf/src/google/protobuf/generated_enum_util.h
@@ -1,6 +1,6 @@
 // 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
@@ -28,21 +28,19 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Author: kenton@google.com (Kenton Varda)
-//  Based on original Protocol Buffers design by
-//  Sanjay Ghemawat, Jeff Dean, and others.
-
-#include <google/protobuf/io/zero_copy_stream.h>
+#ifndef GOOGLE_PROTOBUF_GENERATED_ENUM_UTIL_H__
+#define GOOGLE_PROTOBUF_GENERATED_ENUM_UTIL_H__
 
+#include <google/protobuf/stubs/template_util.h>
 
 namespace google {
 namespace protobuf {
-namespace io {
-
-ZeroCopyInputStream::~ZeroCopyInputStream() {}
-ZeroCopyOutputStream::~ZeroCopyOutputStream() {}
 
+// This type trait can be used to cause templates to only match proto2 enum
+// types.
+template <typename T> struct is_proto_enum : ::google::protobuf::internal::false_type {};
 
-}  // namespace io
 }  // namespace protobuf
+
 }  // namespace google
+#endif  // GOOGLE_PROTOBUF_GENERATED_ENUM_UTIL_H__