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

device/usb/usb_device_handle_android.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 "device/usb/usb_device_handle_android.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "device/usb/usb_device.h"
+#include "device/usb/usb_service.h"
 #include "jni/ChromeUsbConnection_jni.h"
 
 using base::android::ScopedJavaLocalRef;
 
 namespace device {
 
 // static
 scoped_refptr<UsbDeviceHandleAndroid> UsbDeviceHandleAndroid::Create(
     JNIEnv* env,
     scoped_refptr<UsbDevice> device,
-    scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
     const base::android::JavaRef<jobject>& usb_connection) {
   ScopedJavaLocalRef<jobject> wrapper =
       Java_ChromeUsbConnection_create(env, usb_connection);
   // C++ doesn't own this file descriptor so CloseBlocking() is overridden
   // below to release it without closing it.
   base::ScopedFD fd(Java_ChromeUsbConnection_getFileDescriptor(env, wrapper));
-  return make_scoped_refptr(new UsbDeviceHandleAndroid(
-      device, std::move(fd), blocking_task_runner, wrapper));
+  return make_scoped_refptr(
+      new UsbDeviceHandleAndroid(device, std::move(fd), wrapper));
 }
 
 UsbDeviceHandleAndroid::UsbDeviceHandleAndroid(
     scoped_refptr<UsbDevice> device,
     base::ScopedFD fd,
-    scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
     const base::android::JavaRef<jobject>& wrapper)
-    : UsbDeviceHandleUsbfs(device, std::move(fd), blocking_task_runner),
+    : UsbDeviceHandleUsbfs(device,
+                           std::move(fd),
+                           UsbService::CreateBlockingTaskRunner()),
       j_object_(wrapper) {}
 
 UsbDeviceHandleAndroid::~UsbDeviceHandleAndroid() {}
 
 void UsbDeviceHandleAndroid::CloseBlocking() {
   ReleaseFileDescriptor();
   task_runner()->PostTask(
       FROM_HERE, base::Bind(&UsbDeviceHandleAndroid::CloseConnection, this));
 }
 
 void UsbDeviceHandleAndroid::CloseConnection() {
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_ChromeUsbConnection_close(env, j_object_);
   j_object_.Reset();
 }
 
 }  // namespace device