Add best-effort/allow rollback flags on WorkItem.

chrome/installer/util/self_reg_work_item.cc

 // 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.
 
 #include "chrome/installer/util/self_reg_work_item.h"
 
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/installer/util/logging_installer.h"
@@ skipping 72 matching lines @@
     } else {
       LOG(ERROR) << "COM registration export function not found";
     }
     ::FreeLibrary(dll_module);
   } else {
     PLOG(WARNING) << "Failed to load: " << dll_path_;
   }
   return success;
 }
 
-bool SelfRegWorkItem::Do() {
-  bool success = RegisterDll(do_register_);
-  if (ignore_failure_)
-    success = true;
-  return success;
+bool SelfRegWorkItem::DoImpl() {
+  return RegisterDll(do_register_);
 }
 
-void SelfRegWorkItem::Rollback() {
-  if (!ignore_failure_) {
-    RegisterDll(!do_register_);
-  }
+void SelfRegWorkItem::RollbackImpl() {
+  RegisterDll(!do_register_);
 }