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diff --git a/deps/v8/include/v8-microtask-queue.h b/deps/v8/include/v8-microtask-queue.h
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+++ b/deps/v8/include/v8-microtask-queue.h
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+// Copyright 2021 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef INCLUDE_V8_MICROTASKS_QUEUE_H_
+#define INCLUDE_V8_MICROTASKS_QUEUE_H_
+
+#include <stddef.h>
+
+#include <memory>
+
+#include "v8-local-handle.h"  // NOLINT(build/include_directory)
+#include "v8-microtask.h"     // NOLINT(build/include_directory)
+#include "v8config.h"         // NOLINT(build/include_directory)
+
+namespace v8 {
+
+class Function;
+
+namespace internal {
+class Isolate;
+class MicrotaskQueue;
+}  // namespace internal
+
+/**
+ * Represents the microtask queue, where microtasks are stored and processed.
+ * https://html.spec.whatwg.org/multipage/webappapis.html#microtask-queue
+ * https://html.spec.whatwg.org/multipage/webappapis.html#enqueuejob(queuename,-job,-arguments)
+ * https://html.spec.whatwg.org/multipage/webappapis.html#perform-a-microtask-checkpoint
+ *
+ * A MicrotaskQueue instance may be associated to multiple Contexts by passing
+ * it to Context::New(), and they can be detached by Context::DetachGlobal().
+ * The embedder must keep the MicrotaskQueue instance alive until all associated
+ * Contexts are gone or detached.
+ *
+ * Use the same instance of MicrotaskQueue for all Contexts that may access each
+ * other synchronously. E.g. for Web embedding, use the same instance for all
+ * origins that share the same URL scheme and eTLD+1.
+ */
+class V8_EXPORT MicrotaskQueue {
+ public:
+  /**
+   * Creates an empty MicrotaskQueue instance.
+   */
+  static std::unique_ptr<MicrotaskQueue> New(
+      Isolate* isolate, MicrotasksPolicy policy = MicrotasksPolicy::kAuto);
+
+  virtual ~MicrotaskQueue() = default;
+
+  /**
+   * Enqueues the callback to the queue.
+   */
+  virtual void EnqueueMicrotask(Isolate* isolate,
+                                Local<Function> microtask) = 0;
+
+  /**
+   * Enqueues the callback to the queue.
+   */
+  virtual void EnqueueMicrotask(v8::Isolate* isolate,
+                                MicrotaskCallback callback,
+                                void* data = nullptr) = 0;
+
+  /**
+   * Adds a callback to notify the embedder after microtasks were run. The
+   * callback is triggered by explicit RunMicrotasks call or automatic
+   * microtasks execution (see Isolate::SetMicrotasksPolicy).
+   *
+   * Callback will trigger even if microtasks were attempted to run,
+   * but the microtasks queue was empty and no single microtask was actually
+   * executed.
+   *
+   * Executing scripts inside the callback will not re-trigger microtasks and
+   * the callback.
+   */
+  virtual void AddMicrotasksCompletedCallback(
+      MicrotasksCompletedCallbackWithData callback, void* data = nullptr) = 0;
+
+  /**
+   * Removes callback that was installed by AddMicrotasksCompletedCallback.
+   */
+  virtual void RemoveMicrotasksCompletedCallback(
+      MicrotasksCompletedCallbackWithData callback, void* data = nullptr) = 0;
+
+  /**
+   * Runs microtasks if no microtask is running on this MicrotaskQueue instance.
+   */
+  virtual void PerformCheckpoint(Isolate* isolate) = 0;
+
+  /**
+   * Returns true if a microtask is running on this MicrotaskQueue instance.
+   */
+  virtual bool IsRunningMicrotasks() const = 0;
+
+  /**
+   * Returns the current depth of nested MicrotasksScope that has
+   * kRunMicrotasks.
+   */
+  virtual int GetMicrotasksScopeDepth() const = 0;
+
+  MicrotaskQueue(const MicrotaskQueue&) = delete;
+  MicrotaskQueue& operator=(const MicrotaskQueue&) = delete;
+
+ private:
+  friend class internal::MicrotaskQueue;
+  MicrotaskQueue() = default;
+};
+
+/**
+ * This scope is used to control microtasks when MicrotasksPolicy::kScoped
+ * is used on Isolate. In this mode every non-primitive call to V8 should be
+ * done inside some MicrotasksScope.
+ * Microtasks are executed when topmost MicrotasksScope marked as kRunMicrotasks
+ * exits.
+ * kDoNotRunMicrotasks should be used to annotate calls not intended to trigger
+ * microtasks.
+ */
+class V8_EXPORT V8_NODISCARD MicrotasksScope {
+ public:
+  enum Type { kRunMicrotasks, kDoNotRunMicrotasks };
+
+  MicrotasksScope(Isolate* isolate, Type type);
+  MicrotasksScope(Isolate* isolate, MicrotaskQueue* microtask_queue, Type type);
+  ~MicrotasksScope();
+
+  /**
+   * Runs microtasks if no kRunMicrotasks scope is currently active.
+   */
+  static void PerformCheckpoint(Isolate* isolate);
+
+  /**
+   * Returns current depth of nested kRunMicrotasks scopes.
+   */
+  static int GetCurrentDepth(Isolate* isolate);
+
+  /**
+   * Returns true while microtasks are being executed.
+   */
+  static bool IsRunningMicrotasks(Isolate* isolate);
+
+  // Prevent copying.
+  MicrotasksScope(const MicrotasksScope&) = delete;
+  MicrotasksScope& operator=(const MicrotasksScope&) = delete;
+
+ private:
+  internal::Isolate* const isolate_;
+  internal::MicrotaskQueue* const microtask_queue_;
+  bool run_;
+};
+
+}  // namespace v8
+
+#endif  // INCLUDE_V8_MICROTASKS_QUEUE_H_