Store data reduction proxy server in a separate class

components/data_reduction_proxy/proto/client_config.proto

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package data_reduction_proxy;
 
 // The client configuration information for using the Data Saver service.
 message ClientConfig {
   // An opaque per-session key assigned by the server which permits use of the
   // Data Saver HTTP proxy servers.
   optional string session_key = 1;
   // The time at which the client should request a new configuration. The
   // session_key is guaranteed to be valid through this time and may be valid
   // for some time thereafter.
-  optional Timestamp refresh_time = 2;
+  optional Timestamp DEPRECATED_refresh_time = 2 [deprecated = true];
   // The proxy configuration the client should use to connect to the Data Saver
   // service.
   optional ProxyConfig proxy_config = 3;
   // The duration after which the client should request a new configuration. The
   // session_key is guaranteed to be valid through this time and may be valid
   // for some time thereafter. If both refresh_duration and refresh_time are
   // present, refresh_duration should take priority.
   optional Duration refresh_duration = 4;
   // Configuration information for reporting pageload metrics.
   optional PageloadMetricsConfig pageload_metrics_config = 5;
@@ skipping 57 matching lines @@
 message ProxyServer {
   // The scheme of the proxy server.
   enum ProxyScheme {
     // The proxy scheme is unspecified.
     UNSPECIFIED = 0;
     // HTTP
     HTTP = 1;
     // HTTPS
     HTTPS = 2;
     // HTTPS over QUIC
-    QUIC = 3;
+    DEPRECATED_QUIC = 3 [deprecated = true];
+  }
+
+  // The deployment type of the proxy server.
+  enum ProxyType {
+    // The proxy type is unspecified.
+    UNSPECIFIED_TYPE = 0;
+    // Core Google datacenter.
+    CORE = 1;
   }
 
   // The scheme for the proxy server.
   optional ProxyScheme scheme = 1;
   // The host name for the proxy server.
   optional string host = 2;
   // The port number for the proxy server.
   optional int32 port = 3;
+  // The type for the proxy server.
+  optional ProxyType type = 4;
 }
 
 // Request object to create a client configuration object.
 message CreateClientConfigRequest {
   // A previous per-session key that was assigned by the service.
   optional string session_key = 1;
 
   // Build version information.
   optional VersionInfo version_info = 2;
 }
 
 // Build version information.
 message VersionInfo {
   // The client's platform type. See
   // components/data_reduction_proxy/core/common/data_reduction_proxy_util.h for
   // allowed strings in CLIENT_ENUMS_LIST.
   optional string client = 1;
 
   // The build number, e.g. 2171
   optional int32 build = 2;
 
   // The patch number of the chromium client: always a non-negative integer.
   optional int32 patch = 3;
 
   // The production channel, e.g. "canary", "dev", "beta", "stable".
   optional string channel = 4;
 }