[MBI] Remove CleanupTaskRunner

We are going to remove cleanup_task_queue and cleanup_task_runner. The scheduling policy of cleanup_task_queue is the same as the default task queue. We can simply use the (per-isolate) default task queue instead of cleanup_task_queue.

[related design doc section]
https://docs.google.com/document/d/1y-vHkrD1z2RtyWYwT6rJkSLHClYNjDDpUbTtBU7l95A/edit#bookmark=id.i19urefmv8te

Bug: 1105403
Change-Id: I3cd4ddac6f4b44fcb3d9105fd826777246c70131
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2335847Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Alexander Timin <altimin@chromium.org>
Commit-Queue: Minoru Chikamune <chikamune@chromium.org>
Cr-Commit-Position: refs/heads/master@{#794782}

third_party/blink/public/platform/scheduler/web_thread_scheduler.h

@@ -82,9 +82,6 @@ class BLINK_PLATFORM_EXPORT WebThreadScheduler {
 
   virtual scoped_refptr<base::SingleThreadTaskRunner> IPCTaskRunner();
 
-  // Returns the cleanup task runner, which is for cleaning up.
-  virtual scoped_refptr<base::SingleThreadTaskRunner> CleanupTaskRunner();
-
   // Returns a default task runner. This is basically same as the default task
   // runner, but is explicitly allowed to run JavaScript. For the detail, see
   // the comment at blink::ThreadScheduler::DeprecatedDefaultTaskRunner.

third_party/blink/public/platform/task_type.h

@@ -260,7 +260,8 @@ enum class TaskType : unsigned char {
   kMainThreadTaskQueueIdle = 41,
   kMainThreadTaskQueueIPC = 42,
   kMainThreadTaskQueueControl = 43,
-  kMainThreadTaskQueueCleanup = 52,
+  // Removed:
+  // kMainThreadTaskQueueCleanup = 52,
   kMainThreadTaskQueueMemoryPurge = 62,
   kMainThreadTaskQueueNonWaking = 69,
   kCompositorThreadTaskQueueDefault = 45,

third_party/blink/renderer/platform/scheduler/common/dummy_schedulers.cc

@@ -243,11 +243,6 @@ class DummyWebThreadScheduler : public WebThreadScheduler,
     return base::ThreadTaskRunnerHandle::Get();
   }
 
-  scoped_refptr<base::SingleThreadTaskRunner> CleanupTaskRunner() override {
-    DCHECK(WTF::IsMainThread());
-    return base::ThreadTaskRunnerHandle::Get();
-  }
-
   scoped_refptr<base::SingleThreadTaskRunner> V8TaskRunner() override {
     DCHECK(WTF::IsMainThread());
     return base::ThreadTaskRunnerHandle::Get();

third_party/blink/renderer/platform/scheduler/common/web_thread_scheduler.cc

@@ -78,12 +78,6 @@ WebThreadScheduler::IPCTaskRunner() {
   return nullptr;
 }
 
-scoped_refptr<base::SingleThreadTaskRunner>
-WebThreadScheduler::CleanupTaskRunner() {
-  NOTREACHED();
-  return nullptr;
-}
-
 scoped_refptr<base::SingleThreadTaskRunner>
 WebThreadScheduler::DeprecatedDefaultTaskRunner() {
   NOTREACHED();

third_party/blink/renderer/platform/scheduler/main_thread/frame_scheduler_impl.cc

@@ -473,7 +473,6 @@ QueueTraits FrameSchedulerImpl::CreateQueueTraitsForTaskType(TaskType type) {
     case TaskType::kMainThreadTaskQueueIdle:
     case TaskType::kMainThreadTaskQueueIPC:
     case TaskType::kMainThreadTaskQueueControl:
-    case TaskType::kMainThreadTaskQueueCleanup:
     case TaskType::kMainThreadTaskQueueMemoryPurge:
     case TaskType::kCompositorThreadTaskQueueDefault:
     case TaskType::kCompositorThreadTaskQueueInput:

third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl.cc

@@ -234,8 +234,6 @@ MainThreadSchedulerImpl::MainThreadSchedulerImpl(
       MainThreadTaskQueue::QueueType::kV8));
   ipc_task_queue_ = NewTaskQueue(MainThreadTaskQueue::QueueCreationParams(
       MainThreadTaskQueue::QueueType::kIPC));
-  cleanup_task_queue_ = NewTaskQueue(MainThreadTaskQueue::QueueCreationParams(
-      MainThreadTaskQueue::QueueType::kCleanup));
   non_waking_task_queue_ =
       NewTaskQueue(MainThreadTaskQueue::QueueCreationParams(
                        MainThreadTaskQueue::QueueType::kNonWaking)
@@ -249,8 +247,6 @@ MainThreadSchedulerImpl::MainThreadSchedulerImpl(
       TaskType::kMainThreadTaskQueueControl);
   ipc_task_runner_ =
       ipc_task_queue_->CreateTaskRunner(TaskType::kMainThreadTaskQueueIPC);
-  cleanup_task_runner_ = cleanup_task_queue_->CreateTaskRunner(
-      TaskType::kMainThreadTaskQueueCleanup);
   non_waking_task_runner_ = non_waking_task_queue_->CreateTaskRunner(
       TaskType::kMainThreadTaskQueueNonWaking);
 
@@ -659,11 +655,6 @@ MainThreadSchedulerImpl::IPCTaskRunner() {
   return ipc_task_runner_;
 }
 
-scoped_refptr<base::SingleThreadTaskRunner>
-MainThreadSchedulerImpl::CleanupTaskRunner() {
-  return cleanup_task_runner_;
-}
-
 scoped_refptr<base::SingleThreadTaskRunner>
 MainThreadSchedulerImpl::DeprecatedDefaultTaskRunner() {
   return helper_.DeprecatedDefaultTaskRunner();

third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl.h

@@ -161,7 +161,6 @@ class PLATFORM_EXPORT MainThreadSchedulerImpl
   std::unique_ptr<WebWidgetScheduler> CreateWidgetScheduler() override;
   // Note: this is also shared by the ThreadScheduler interface.
   scoped_refptr<base::SingleThreadTaskRunner> IPCTaskRunner() override;
-  scoped_refptr<base::SingleThreadTaskRunner> CleanupTaskRunner() override;
   scoped_refptr<base::SingleThreadTaskRunner> NonWakingTaskRunner() override;
   scoped_refptr<base::SingleThreadTaskRunner> DeprecatedDefaultTaskRunner()
       override;
@@ -839,7 +838,6 @@ class PLATFORM_EXPORT MainThreadSchedulerImpl
 
   scoped_refptr<MainThreadTaskQueue> v8_task_queue_;
   scoped_refptr<MainThreadTaskQueue> ipc_task_queue_;
-  scoped_refptr<MainThreadTaskQueue> cleanup_task_queue_;
   scoped_refptr<MainThreadTaskQueue> memory_purge_task_queue_;
   scoped_refptr<MainThreadTaskQueue> non_waking_task_queue_;
 
@@ -847,7 +845,6 @@ class PLATFORM_EXPORT MainThreadSchedulerImpl
   scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> control_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> ipc_task_runner_;
-  scoped_refptr<base::SingleThreadTaskRunner> cleanup_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> non_waking_task_runner_;
 
   MemoryPurgeManager memory_purge_manager_;

third_party/blink/renderer/platform/scheduler/main_thread/main_thread_task_queue.cc

@@ -55,8 +55,6 @@ const char* MainThreadTaskQueue::NameForQueueType(
       return "input_tq";
     case MainThreadTaskQueue::QueueType::kDetached:
       return "detached_tq";
-    case MainThreadTaskQueue::QueueType::kCleanup:
-      return "cleanup_tq";
     case MainThreadTaskQueue::QueueType::kOther:
       return "other_tq";
     case MainThreadTaskQueue::QueueType::kWebScheduling:
@@ -93,7 +91,6 @@ bool MainThreadTaskQueue::IsPerFrameTaskQueue(
     case MainThreadTaskQueue::QueueType::kIPC:
     case MainThreadTaskQueue::QueueType::kInput:
     case MainThreadTaskQueue::QueueType::kDetached:
-    case MainThreadTaskQueue::QueueType::kCleanup:
     case MainThreadTaskQueue::QueueType::kNonWaking:
     case MainThreadTaskQueue::QueueType::kOther:
       return false;
@@ -115,7 +112,6 @@ MainThreadTaskQueue::QueueClass MainThreadTaskQueue::QueueClassForQueueType(
     case QueueType::kV8:
     case QueueType::kIPC:
     case QueueType::kNonWaking:
-    case QueueType::kCleanup:
       return QueueClass::kNone;
     case QueueType::kFrameLoading:
     case QueueType::kFrameLoadingControl:

third_party/blink/renderer/platform/scheduler/main_thread/main_thread_task_queue.h

@@ -71,8 +71,7 @@ class PLATFORM_EXPORT MainThreadTaskQueue
     // TODO(altimin): Move to the top when histogram is renumbered.
     kDetached = 19,
 
-    kCleanup = 20,
-
+    // 20 : kCleanup, obsolete.
     // 21 : kWebSchedulingUserInteraction, obsolete.
     // 22 : kWebSchedulingBestEffort, obsolete.
 

third_party/blink/renderer/platform/scheduler/main_thread/task_type_names.cc

@@ -105,8 +105,6 @@ const char* TaskTypeNames::TaskTypeToString(TaskType task_type) {
       return "MainThreadTaskQueueIPC";
     case TaskType::kMainThreadTaskQueueControl:
       return "MainThreadTaskQueueControl";
-    case TaskType::kMainThreadTaskQueueCleanup:
-      return "MainThreadTaskQueueCleanup";
     case TaskType::kMainThreadTaskQueueMemoryPurge:
       return "MainThreadTaskQueueMemoryPurge";
     case TaskType::kMainThreadTaskQueueNonWaking:

third_party/blink/renderer/platform/scheduler/test/renderer_scheduler_test_support.cc

@@ -32,10 +32,6 @@ class SimpleMockMainThreadScheduler : public WebMockThreadScheduler {
     return base::ThreadTaskRunnerHandle::Get();
   }
 
-  scoped_refptr<base::SingleThreadTaskRunner> CleanupTaskRunner() override {
-    return base::ThreadTaskRunnerHandle::Get();
-  }
-
   std::unique_ptr<Thread> CreateMainThread() override {
     return simple_thread_scheduler_->CreateMainThread();
   }

third_party/blink/renderer/platform/scheduler/worker/worker_scheduler.cc

@@ -196,7 +196,6 @@ scoped_refptr<base::SingleThreadTaskRunner> WorkerScheduler::GetTaskRunner(
     case TaskType::kMainThreadTaskQueueIdle:
     case TaskType::kMainThreadTaskQueueIPC:
     case TaskType::kMainThreadTaskQueueControl:
-    case TaskType::kMainThreadTaskQueueCleanup:
     case TaskType::kMainThreadTaskQueueMemoryPurge:
     case TaskType::kMainThreadTaskQueueNonWaking:
     case TaskType::kCompositorThreadTaskQueueDefault: