third_party/protobuf: Update to HEAD (f52e188fe4)

third_party/protobuf/src/google/protobuf/api.proto

 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
 // 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.
@@ skipping 21 matching lines @@
 
 package google.protobuf;
 
 import "google/protobuf/source_context.proto";
 import "google/protobuf/type.proto";
 
 option csharp_namespace = "Google.Protobuf.WellKnownTypes";
 option java_package = "com.google.protobuf";
 option java_outer_classname = "ApiProto";
 option java_multiple_files = true;
-option java_generate_equals_and_hash = true;
 option objc_class_prefix = "GPB";
+option go_package = "google.golang.org/genproto/protobuf/api;api";
 
 // Api is a light-weight descriptor for a protocol buffer service.
 message Api {
 
   // The fully qualified name of this api, including package name
   // followed by the api's simple name.
   string name = 1;
 
   // The methods of this api, in unspecified order.
   repeated Method methods = 2;
@@ skipping 139 matching lines @@
 //       ...
 //     }
 message Mixin {
   // The fully qualified name of the API which is included.
   string name = 1;
 
   // If non-empty specifies a path under which inherited HTTP paths
   // are rooted.
   string root = 2;
 }