Introduce v8::MicrotasksScope.

test/cctest/test-thread-termination.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 385 matching lines @@
   CHECK(v8::Isolate::GetCurrent()->IsExecutionTerminating());
 }
 
 
 TEST(TerminateFromOtherThreadWhileMicrotaskRunning) {
   semaphore = new v8::base::Semaphore(0);
   TerminatorThread thread(CcTest::i_isolate());
   thread.Start();
 
   v8::Isolate* isolate = CcTest::isolate();
-  isolate->SetAutorunMicrotasks(false);
+  isolate->SetMicrotasksPolicy(v8::MicrotasksPolicy::kExplicit);
   v8::HandleScope scope(isolate);
   v8::Local<v8::ObjectTemplate> global =
       CreateGlobalTemplate(CcTest::isolate(), Signal, DoLoop);
   v8::Local<v8::Context> context =
       v8::Context::New(CcTest::isolate(), NULL, global);
   v8::Context::Scope context_scope(context);
   isolate->EnqueueMicrotask(
       v8::Function::New(isolate->GetCurrentContext(), MicrotaskLoopForever)
           .ToLocalChecked());
   // The second task should never be run because we bail out if we're
@@ skipping 142 matching lines @@
   CHECK(value->IsFunction());
   // The first stack check after terminate has been re-requested fails.
   CHECK(CompileRun("1 + 1").IsEmpty());
   CHECK(!isolate->IsExecutionTerminating());
   // V8 then recovers.
   v8::Maybe<int32_t> result = CompileRun("2 + 2")->Int32Value(
       v8::Isolate::GetCurrent()->GetCurrentContext());
   CHECK_EQ(4, result.FromJust());
   CHECK(!isolate->IsExecutionTerminating());
 }