Avoid useless SYNC_CYCLE_CONTINUATION sync cycle

chrome/browser/sync/engine/syncer_proto_util.h

 // Copyright (c) 2011 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 CHROME_BROWSER_SYNC_ENGINE_SYNCER_PROTO_UTIL_H_
 #define CHROME_BROWSER_SYNC_ENGINE_SYNCER_PROTO_UTIL_H_
 #pragma once
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
 #include "base/time.h"
 #include "chrome/browser/sync/sessions/sync_session.h"
+#include "chrome/browser/sync/engine/syncer_error.h"
 #include "chrome/browser/sync/syncable/blob.h"
 #include "chrome/browser/sync/syncable/model_type.h"
 
 namespace syncable {
 class Directory;
 class Entry;
 }  // namespace syncable
 
 namespace sync_pb {
 class ClientToServerResponse;
@@ skipping 11 matching lines @@
 class ServerConnectionManager;
 class SyncEntity;
 class CommitResponse_EntryResponse;
 
 class SyncerProtoUtil {
  public:
   // Posts the given message and fills the buffer with the returned value.
   // Returns true on success.  Also handles store birthday verification:
   // session->status()->syncer_stuck_ is set true if the birthday is
   // incorrect.  A false value will always be returned if birthday is bad.
-  static bool PostClientToServerMessage(
+  static SyncerError PostClientToServerMessage(
       const ClientToServerMessage& msg,
       sync_pb::ClientToServerResponse* response,
       sessions::SyncSession* session);
 
   // Compares a syncable Entry to SyncEntity, returns true iff the data is
   // identical.
   //
   // TODO(sync): The places where this function is used are arguable big causes
   // of the fragility, because there's a tendency to freak out the moment the
   // local and server values diverge. However, this almost always indicates a
@@ skipping 73 matching lines @@
   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, VerifyResponseBirthday);
   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, HandleThrottlingNoDatatypes);
   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, HandleThrottlingWithDatatypes);
 
   DISALLOW_COPY_AND_ASSIGN(SyncerProtoUtil);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_ENGINE_SYNCER_PROTO_UTIL_H_