Use the task scheduler for blocking tasks in the USB service on Linux

device/usb/usb_service_unittest.cc

 // 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 <memory>
 
 #include "base/bind.h"
-#include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/scoped_feature_list.h"
+#include "base/test/scoped_task_environment.h"
 #include "base/test/test_io_thread.h"
 #include "device/base/features.h"
 #include "device/test/test_device_client.h"
 #include "device/test/usb_test_gadget.h"
 #include "device/usb/usb_device.h"
 #include "device/usb/usb_device_handle.h"
 #include "device/usb/usb_service.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace device {
 
 namespace {
 
 class UsbServiceTest : public ::testing::Test {
  public:
+  UsbServiceTest()
+      : scoped_task_environment_(
+            base::test::ScopedTaskEnvironment::MainThreadType::UI),
+        io_thread_(base::TestIOThread::kAutoStart) {}
+
   void SetUp() override {
-    message_loop_.reset(new base::MessageLoopForUI);
-    io_thread_.reset(new base::TestIOThread(base::TestIOThread::kAutoStart));
-    device_client_.reset(new TestDeviceClient(io_thread_->task_runner()));
+    device_client_.reset(new TestDeviceClient(io_thread_.task_runner()));
   }
 
  protected:
-  std::unique_ptr<base::MessageLoop> message_loop_;
-  std::unique_ptr<base::TestIOThread> io_thread_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
+  base::TestIOThread io_thread_;
   std::unique_ptr<TestDeviceClient> device_client_;
 };
 
 void OnGetDevices(const base::Closure& quit_closure,
                   const std::vector<scoped_refptr<UsbDevice>>& devices) {
   quit_closure.Run();
 }
 
 void OnOpen(scoped_refptr<UsbDeviceHandle>* output,
             const base::Closure& quit_closure,
@@ skipping 24 matching lines @@
     service->GetDevices(base::Bind(&OnGetDevices, loop.QuitClosure()));
     loop.Run();
   }
 }
 #endif  // defined(OS_WIN)
 
 TEST_F(UsbServiceTest, ClaimGadget) {
   if (!UsbTestGadget::IsTestEnabled()) return;
 
   std::unique_ptr<UsbTestGadget> gadget =
-      UsbTestGadget::Claim(io_thread_->task_runner());
+      UsbTestGadget::Claim(io_thread_.task_runner());
   ASSERT_TRUE(gadget);
 
   scoped_refptr<UsbDevice> device = gadget->GetDevice();
   ASSERT_EQ("Google Inc.", base::UTF16ToUTF8(device->manufacturer_string()));
   ASSERT_EQ("Test Gadget (default state)",
             base::UTF16ToUTF8(device->product_string()));
 }
 
 TEST_F(UsbServiceTest, DisconnectAndReconnect) {
   if (!UsbTestGadget::IsTestEnabled()) return;
 
   std::unique_ptr<UsbTestGadget> gadget =
-      UsbTestGadget::Claim(io_thread_->task_runner());
+      UsbTestGadget::Claim(io_thread_.task_runner());
   ASSERT_TRUE(gadget);
   ASSERT_TRUE(gadget->Disconnect());
   ASSERT_TRUE(gadget->Reconnect());
 }
 
 TEST_F(UsbServiceTest, Shutdown) {
   if (!UsbTestGadget::IsTestEnabled())
     return;
 
   std::unique_ptr<UsbTestGadget> gadget =
-      UsbTestGadget::Claim(io_thread_->task_runner());
+      UsbTestGadget::Claim(io_thread_.task_runner());
   ASSERT_TRUE(gadget);
 
   base::RunLoop loop;
   scoped_refptr<UsbDeviceHandle> device_handle;
   gadget->GetDevice()->Open(
       base::Bind(&OnOpen, &device_handle, loop.QuitClosure()));
   loop.Run();
   ASSERT_TRUE(device_handle);
 
   // Shut down the USB service while the device handle is still open.
   device_client_.reset();
   EXPECT_FALSE(device_handle->GetDevice());
 }
 
 }  // namespace
 
 }  // namespace device