Update //third_party/protobuf to version 3.

third_party/protobuf/objectivec/GPBUnknownFieldSet_PackagePrivate.h

Index: third_party/protobuf/objectivec/GPBUnknownFieldSet_PackagePrivate.h
diff --git a/third_party/protobuf/python/google/protobuf/internal/more_extensions.proto b/third_party/protobuf/objectivec/GPBUnknownFieldSet_PackagePrivate.h
similarity index 64%
copy from third_party/protobuf/python/google/protobuf/internal/more_extensions.proto
copy to third_party/protobuf/objectivec/GPBUnknownFieldSet_PackagePrivate.h
index e2d97010450d32f2d1dd7b3ec0d2d05bf93435cb..e27127ad1d1e40c8bbc9a692f434d807c9b3f2e7 100644
--- a/third_party/protobuf/python/google/protobuf/internal/more_extensions.proto
+++ b/third_party/protobuf/objectivec/GPBUnknownFieldSet_PackagePrivate.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
@@ -28,31 +28,34 @@
 // (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: robinson@google.com (Will Robinson)
+#import <Foundation/Foundation.h>
 
+#import "GPBUnknownFieldSet.h"
 
-package google.protobuf.internal;
+@class GPBCodedOutputStream;
+@class GPBCodedInputStream;
 
+@interface GPBUnknownFieldSet ()
 
-message TopLevelMessage {
-  optional ExtendedMessage submessage = 1;
-}
++ (BOOL)isFieldTag:(int32_t)tag;
 
+- (NSData *)data;
 
-message ExtendedMessage {
-  extensions 1 to max;
-}
+- (size_t)serializedSize;
+- (size_t)serializedSizeAsMessageSet;
 
+- (void)writeToCodedOutputStream:(GPBCodedOutputStream *)output;
+- (void)writeAsMessageSetTo:(GPBCodedOutputStream *)output;
 
-message ForeignMessage {
-  optional int32 foreign_message_int = 1;
-}
+- (void)mergeUnknownFields:(GPBUnknownFieldSet *)other;
 
+- (void)mergeFromCodedInputStream:(GPBCodedInputStream *)input;
+- (void)mergeFromData:(NSData *)data;
 
-extend ExtendedMessage {
-  optional int32 optional_int_extension = 1;
-  optional ForeignMessage optional_message_extension = 2;
+- (void)mergeVarintField:(int32_t)number value:(int32_t)value;
+- (BOOL)mergeFieldFrom:(int32_t)tag input:(GPBCodedInputStream *)input;
+- (void)mergeMessageSetMessage:(int32_t)number data:(NSData *)messageData;
 
-  repeated int32 repeated_int_extension = 3;
-  repeated ForeignMessage repeated_message_extension = 4;
-}
+- (void)addUnknownMapEntry:(int32_t)fieldNum value:(NSData *)data;
+
+@end