Use timer task runner for V8PerIsolate tasks

extensions/renderer/api_binding_test.cc

 // Copyright 2016 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 "extensions/renderer/api_binding_test.h"
 
 #include "base/memory/ptr_util.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "gin/array_buffer.h"
 #include "gin/public/context_holder.h"
 #include "gin/public/isolate_holder.h"
 #include "gin/v8_initializer.h"
 
 namespace extensions {
 
 APIBindingTest::APIBindingTest() {}
 APIBindingTest::~APIBindingTest() {}
 
 void APIBindingTest::SetUp() {
   // Much of this initialization is stolen from the somewhat-similar
   // gin::V8Test.
 #ifdef V8_USE_EXTERNAL_STARTUP_DATA
   gin::V8Initializer::LoadV8Snapshot();
   gin::V8Initializer::LoadV8Natives();
 #endif
 
   gin::IsolateHolder::Initialize(gin::IsolateHolder::kStrictMode,
                                  gin::IsolateHolder::kStableV8Extras,
                                  gin::ArrayBufferAllocator::SharedInstance());
 
-  isolate_holder_ = base::MakeUnique<gin::IsolateHolder>();
+  isolate_holder_ =
+      base::MakeUnique<gin::IsolateHolder>(base::ThreadTaskRunnerHandle::Get());
   isolate()->Enter();
 
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context = v8::Context::New(isolate());
   context->Enter();
   context_holder_ = base::MakeUnique<gin::ContextHolder>(isolate());
   context_holder_->SetContext(context);
 }
 
 void APIBindingTest::TearDown() {
@@ skipping 41 matching lines @@
 
 void APIBindingTest::DisposeContext() {
   context_holder_.reset();
 }
 
 v8::Isolate* APIBindingTest::isolate() {
   return isolate_holder_->isolate();
 }
 
 }  // namespace extensions