Don't drop debug_info when posting to sync server fails

sync/test/engine/mock_connection_manager.h

 // Copyright (c) 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.
 //
 // Mock ServerConnectionManager class for use in client unit tests.
 
 #ifndef SYNC_TEST_ENGINE_MOCK_CONNECTION_MANAGER_H_
 #define SYNC_TEST_ENGINE_MOCK_CONNECTION_MANAGER_H_
 
 #include <bitset>
@@ skipping 176 matching lines @@
   const std::vector<sync_pb::CommitResponse*>& commit_responses() const {
     return commit_responses_.get();
   }
   // Retrieve the last sent commit message.
   const sync_pb::CommitMessage& last_sent_commit() const;
 
   // Retrieve the last returned commit response.
   const sync_pb::CommitResponse& last_commit_response() const;
 
   // Retrieve the last request submitted to the server (regardless of type).
-  const sync_pb::ClientToServerMessage& last_request() const {
-    return last_request_;
-  }
+  const sync_pb::ClientToServerMessage& last_request() const;
+
+  // Retrieve the cumulative collection of all requests sent by clients.
+  const std::vector<sync_pb::ClientToServerMessage>& requests() const;
 
   void set_conflict_all_commits(bool value) {
     conflict_all_commits_ = value;
   }
   void set_next_new_id(int value) {
     next_new_id_ = value;
   }
   void set_conflict_n_commits(int value) {
     conflict_n_commits_ = value;
   }
@@ skipping 178 matching lines @@
   // If this option is set to true, then the MockConnectionManager will
   // use the older sync_pb::SyncEntity_BookmarkData-style protocol.
   bool use_legacy_bookmarks_protocol_;
 
   ModelTypeSet expected_filter_;
 
   int num_get_updates_requests_;
 
   std::string next_token_;
 
-  sync_pb::ClientToServerMessage last_request_;
+  std::vector<sync_pb::ClientToServerMessage> requests_;
 
   DISALLOW_COPY_AND_ASSIGN(MockConnectionManager);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_TEST_ENGINE_MOCK_CONNECTION_MANAGER_H_