Implement basic USB device enumeration on Android.

device/usb/usb_device_impl.h

Index: device/usb/usb_device_impl.h
diff --git a/device/usb/usb_device_impl.h b/device/usb/usb_device_impl.h
index ccd119ae7cfb996c7d8ba39fdd5024e5366a4578..e6145c89ac2a026b9501620a5539a05c9c5a7d90 100644
--- a/device/usb/usb_device_impl.h
+++ b/device/usb/usb_device_impl.h
@@ -5,6 +5,7 @@
 #ifndef DEVICE_USB_USB_DEVICE_IMPL_H_
 #define DEVICE_USB_USB_DEVICE_IMPL_H_
 
+#include <string>
 #include <vector>
 
 #include "base/callback.h"
@@ -41,7 +42,6 @@ class UsbDeviceImpl : public UsbDevice {
   void CheckUsbAccess(const ResultCallback& callback) override;
 #endif  // OS_CHROMEOS
   void Open(const OpenCallback& callback) override;
-  bool Close(scoped_refptr<UsbDeviceHandle> handle) override;
   const UsbConfigDescriptor* GetActiveConfiguration() override;
 
   // These functions are used during enumeration only. The values must not
@@ -83,6 +83,7 @@ class UsbDeviceImpl : public UsbDevice {
   void ReadAllConfigurations();
 
   // Called by UsbDeviceHandleImpl.
+  void Close(scoped_refptr<UsbDeviceHandle> handle);
   void RefreshActiveConfiguration();
 
  private: