Move UsbService to its own component.

chrome/browser/usb/usb_context_unittest.cc

-// Copyright 2013 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 "chrome/browser/usb/usb_context.h"
-
-#include "base/threading/platform_thread.h"
-#include "build/build_config.h"
-#include "testing/gtest/include/gtest/gtest.h"
-#include "third_party/libusb/src/libusb/libusb.h"
-
-namespace {
-
-class UsbContextTest : public testing::Test {
- protected:
-  class UsbContextForTest : public UsbContext {
-   public:
-    explicit UsbContextForTest(PlatformUsbContext context)
-        : UsbContext(context) {}
-   private:
-    virtual ~UsbContextForTest() {}
-    DISALLOW_COPY_AND_ASSIGN(UsbContextForTest);
-  };
-};
-
-}  // namespace
-
-#if defined(OS_LINUX)
-// Linux trybot does not support usb.
-#define MAYBE_GracefulShutdown DISABLED_GracefulShutdown
-#elif defined(OS_ANDROID)
-// Android build does not include usb support.
-#define MAYBE_GracefulShutdown DISABLED_GracefulShutdown
-#else
-#define MAYBE_GracefulShutdown GracefulShutdown
-#endif
-
-TEST_F(UsbContextTest, MAYBE_GracefulShutdown) {
-  base::TimeTicks start = base::TimeTicks::Now();
-  {
-    PlatformUsbContext platform_context;
-    ASSERT_EQ(LIBUSB_SUCCESS, libusb_init(&platform_context));
-    scoped_refptr<UsbContextForTest> context(
-        new UsbContextForTest(platform_context));
-  }
-  base::TimeDelta elapse = base::TimeTicks::Now() - start;
-  if (elapse > base::TimeDelta::FromSeconds(2)) {
-    FAIL();
-  }
-}