[scheduler] Add TaskQueue::Observer

third_party/WebKit/Source/platform/scheduler/base/virtual_time_domain.cc

 // Copyright 2015 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 "platform/scheduler/base/virtual_time_domain.h"
 
 #include "base/bind.h"
 #include "platform/scheduler/base/task_queue_impl.h"
 #include "platform/scheduler/base/task_queue_manager.h"
 #include "platform/scheduler/base/task_queue_manager_delegate.h"
 
 namespace blink {
 namespace scheduler {
 
-VirtualTimeDomain::VirtualTimeDomain(TimeDomain::Observer* observer,
-                                     base::TimeTicks initial_time)
-    : TimeDomain(observer), now_(initial_time), task_queue_manager_(nullptr) {}
+VirtualTimeDomain::VirtualTimeDomain(base::TimeTicks initial_time)
+    : now_(initial_time), task_queue_manager_(nullptr) {}
 
 VirtualTimeDomain::~VirtualTimeDomain() {}
 
 void VirtualTimeDomain::OnRegisterWithTaskQueueManager(
     TaskQueueManager* task_queue_manager) {
   task_queue_manager_ = task_queue_manager;
   DCHECK(task_queue_manager_);
 }
 
 LazyNow VirtualTimeDomain::CreateLazyNow() const {
@@ skipping 34 matching lines @@
 void VirtualTimeDomain::RequestDoWork() {
   task_queue_manager_->MaybeScheduleImmediateWork(FROM_HERE);
 }
 
 const char* VirtualTimeDomain::GetName() const {
   return "VirtualTimeDomain";
 }
 
 }  // namespace scheduler
 }  // namespace blink