Update //third_party/protobuf to version 3.

third_party/protobuf/objectivec/GPBProtocolBuffers.m

 // 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
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (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.
+// If you want to build protocol buffers in your own project without adding the
+// project dependency, you can just add this file.
 
-#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_DOC_COMMENT_H__
-#define GOOGLE_PROTOBUF_COMPILER_JAVA_DOC_COMMENT_H__
+#import "GPBArray.m"
+#import "GPBCodedInputStream.m"
+#import "GPBCodedOutputStream.m"
+#import "GPBDescriptor.m"
+#import "GPBDictionary.m"
+#import "GPBExtensionInternals.m"
+#import "GPBExtensionRegistry.m"
+#import "GPBMessage.m"
+#import "GPBRootObject.m"
+#import "GPBUnknownField.m"
+#import "GPBUnknownFieldSet.m"
+#import "GPBUtilities.m"
+#import "GPBWellKnownTypes.m"
+#import "GPBWireFormat.m"
 
-#include <google/protobuf/descriptor.h>
+#import "google/protobuf/Descriptor.pbobjc.m"
 
-namespace google {
-namespace protobuf {
-  namespace io {
-    class Printer;             // printer.h
-  }
-}
-
-namespace protobuf {
-namespace compiler {
-namespace java {
-
-void WriteMessageDocComment(io::Printer* printer, const Descriptor* message);
-void WriteFieldDocComment(io::Printer* printer, const FieldDescriptor* field);
-void WriteEnumDocComment(io::Printer* printer, const EnumDescriptor* enum_);
-void WriteEnumValueDocComment(io::Printer* printer,
-                              const EnumValueDescriptor* value);
-void WriteServiceDocComment(io::Printer* printer,
-                            const ServiceDescriptor* service);
-void WriteMethodDocComment(io::Printer* printer,
-                           const MethodDescriptor* method);
-
-// Exposed for testing only.
-string EscapeJavadoc(const string& input);
-
-}  // namespace java
-}  // namespace compiler
-}  // namespace protobuf
-
-}  // namespace google
-#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_DOC_COMMENT_H__
+// Duration and Timestamp are #imported into GPBWellKnownTypes.m to the
+// Objective C categories added will always be linked in with the classes.
+#import "google/protobuf/Any.pbobjc.m"
+#import "google/protobuf/Api.pbobjc.m"
+// #import "google/protobuf/Duration.pbobjc.m"
+#import "google/protobuf/Empty.pbobjc.m"
+#import "google/protobuf/FieldMask.pbobjc.m"
+#import "google/protobuf/SourceContext.pbobjc.m"
+#import "google/protobuf/Struct.pbobjc.m"
+// #import "google/protobuf/Timestamp.pbobjc.m"
+#import "google/protobuf/Type.pbobjc.m"
+#import "google/protobuf/Wrappers.pbobjc.m"