[Sync] Sync should run canary cycle after any network related error

sync/engine/net/server_connection_manager.h

 // Copyright 2012 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.
 
 #ifndef SYNC_ENGINE_NET_SERVER_CONNECTION_MANAGER_H_
 #define SYNC_ENGINE_NET_SERVER_CONNECTION_MANAGER_H_
 
 #include <stdint.h>
 
 #include <iosfwd>
@@ skipping 73 matching lines @@
   // The size of a download request's payload.
   int64_t payload_length;
 
   // Identifies the type of failure, if any.
   ServerConnectionCode server_status;
 
   HttpResponse();
 
   static const char* GetServerConnectionCodeString(
       ServerConnectionCode code);
-
-  static ServerConnectionCode ServerConnectionCodeFromNetError(
-      int error_code);
 };
 
 struct ServerConnectionEvent {
   HttpResponse::ServerConnectionCode connection_code;
   explicit ServerConnectionEvent(HttpResponse::ServerConnectionCode code) :
       connection_code(code) {}
 };
 
 class SYNC_EXPORT ServerConnectionEventListener {
  public:
@@ skipping 209 matching lines @@
   bool signal_handler_registered_;
 
   DISALLOW_COPY_AND_ASSIGN(ServerConnectionManager);
 };
 
 std::ostream& operator<<(std::ostream& s, const struct HttpResponse& hr);
 
 }  // namespace syncer
 
 #endif  // SYNC_ENGINE_NET_SERVER_CONNECTION_MANAGER_H_