Revert of [sync] Add Sessions integration tests

chrome/browser/sync/test/integration/session_hierarchy_match_checker.cc

-// Copyright (c) 2017 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.
-
-#include "chrome/browser/sync/test/integration/session_hierarchy_match_checker.h"
-
-SessionHierarchyMatchChecker::SessionHierarchyMatchChecker(
-    const fake_server::SessionsHierarchy& sessions_hierarchy,
-    browser_sync::ProfileSyncService* service,
-    fake_server::FakeServer* fake_server)
-    : SingleClientStatusChangeChecker(service),
-      sessions_hierarchy_(sessions_hierarchy),
-      verifier_(fake_server) {}
-
-bool SessionHierarchyMatchChecker::IsExitConditionSatisfied() {
-  return verifier_.VerifySessions(sessions_hierarchy_);
-}
-
-std::string SessionHierarchyMatchChecker::GetDebugMessage() const {
-  return "Waiting for matching sessions hierarchy to be reflected in fake "
-         "server";
-}