Implement basic USB device enumeration on Android.

device/usb/usb_device_impl.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 "device/usb/usb_device_impl.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
@@ skipping 186 matching lines @@
   client->OpenPath(
       device_path_,
       base::Bind(&UsbDeviceImpl::OnOpenRequestComplete, this, callback));
 #else
   blocking_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&UsbDeviceImpl::OpenOnBlockingThread, this, callback));
 #endif  // defined(OS_CHROMEOS)
 }
 
-bool UsbDeviceImpl::Close(scoped_refptr<UsbDeviceHandle> handle) {
+void UsbDeviceImpl::Close(scoped_refptr<UsbDeviceHandle> handle) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   for (HandlesVector::iterator it = handles_.begin(); it != handles_.end();
        ++it) {
     if (it->get() == handle.get()) {
       (*it)->InternalClose();
       handles_.erase(it);
-      return true;
+      return;
     }
   }
-  return false;
 }
 
 const UsbConfigDescriptor* UsbDeviceImpl::GetActiveConfiguration() {
   DCHECK(thread_checker_.CalledOnValidThread());
   return active_configuration_;
 }
 
 void UsbDeviceImpl::OnDisconnect() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
@@ skipping 102 matching lines @@
 void UsbDeviceImpl::Opened(PlatformUsbDeviceHandle platform_handle,
                            const OpenCallback& callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
   scoped_refptr<UsbDeviceHandleImpl> device_handle = new UsbDeviceHandleImpl(
       context_, this, platform_handle, blocking_task_runner_);
   handles_.push_back(device_handle);
   callback.Run(device_handle);
 }
 
 }  // namespace device