Run microtasks at the end of each worker task.

Source/bindings/core/v8/ScriptPromiseResolver.cpp

 // Copyright 2014 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 "config.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 
 #include "bindings/core/v8/V8RecursionScope.h"
 
 namespace blink {
@@ skipping 46 matching lines @@
     ASSERT(m_state == Resolving || m_state == Rejecting);
     ScriptState::Scope scope(m_scriptState.get());
     resolveOrRejectImmediately();
 }
 
 void ScriptPromiseResolver::resolveOrRejectImmediately()
 {
     ASSERT(!executionContext()->activeDOMObjectsAreStopped());
     ASSERT(!executionContext()->activeDOMObjectsAreSuspended());
     {
-        // FIXME: The V8RecursionScope is only necessary to force microtask delivery for promises
-        // resolved or rejected in workers. It can be removed once worker threads run microtasks
-        // at the end of every task (rather than just the main thread).
-        V8RecursionScope scope(m_scriptState->isolate(), m_scriptState->executionContext());
         if (m_state == Resolving) {
             m_resolver.resolve(m_value.newLocal(m_scriptState->isolate()));
         } else {
             ASSERT(m_state == Rejecting);
             m_resolver.reject(m_value.newLocal(m_scriptState->isolate()));
         }
     }
     clear();
 }
 
@@ skipping 12 matching lines @@
     // |this| may be deleted here, but it is safe to check |state| because
     // it doesn't depend on |this|. When |this| is deleted, |state| can't be
     // |Resolving| nor |Rejecting| and hence |this->deref()| can't be executed.
     if (state == Resolving || state == Rejecting) {
         // |ref| was called in |resolveOrReject|.
         deref();
     }
 }
 
 } // namespace blink