Add a service to track devices selected by the user.

device/usb/usb_device_handle.h

Index: device/usb/usb_device_handle.h
diff --git a/device/usb/usb_device_handle.h b/device/usb/usb_device_handle.h
index 08d97f84789aa11231eb2d80ca1f2043339a183e..be5a30ee400ec79b7255ec255c6a9260650acad2 100644
--- a/device/usb/usb_device_handle.h
+++ b/device/usb/usb_device_handle.h
@@ -61,38 +61,38 @@ class UsbDeviceHandle : public base::RefCountedThreadSafe<UsbDeviceHandle> {
   virtual bool GetSerial(base::string16* serial) = 0;
 
   // Async IO. Can be called on any thread.
-  virtual void ControlTransfer(const UsbEndpointDirection direction,
-                               const TransferRequestType request_type,
-                               const TransferRecipient recipient,
-                               const uint8 request,
-                               const uint16 value,
-                               const uint16 index,
+  virtual void ControlTransfer(UsbEndpointDirection direction,
+                               TransferRequestType request_type,
+                               TransferRecipient recipient,
+                               uint8 request,
+                               uint16 value,
+                               uint16 index,
                                net::IOBuffer* buffer,
-                               const size_t length,
-                               const unsigned int timeout,
+                               size_t length,
+                               unsigned int timeout,
                                const UsbTransferCallback& callback) = 0;
 
-  virtual void BulkTransfer(const UsbEndpointDirection direction,
-                            const uint8 endpoint,
+  virtual void BulkTransfer(UsbEndpointDirection direction,
+                            uint8 endpoint,
                             net::IOBuffer* buffer,
-                            const size_t length,
-                            const unsigned int timeout,
+                            size_t length,
+                            unsigned int timeout,
                             const UsbTransferCallback& callback) = 0;
 
-  virtual void InterruptTransfer(const UsbEndpointDirection direction,
-                                 const uint8 endpoint,
+  virtual void InterruptTransfer(UsbEndpointDirection direction,
+                                 uint8 endpoint,
                                  net::IOBuffer* buffer,
-                                 const size_t length,
-                                 const unsigned int timeout,
+                                 size_t length,
+                                 unsigned int timeout,
                                  const UsbTransferCallback& callback) = 0;
 
-  virtual void IsochronousTransfer(const UsbEndpointDirection direction,
-                                   const uint8 endpoint,
+  virtual void IsochronousTransfer(UsbEndpointDirection direction,
+                                   uint8 endpoint,
                                    net::IOBuffer* buffer,
-                                   const size_t length,
-                                   const unsigned int packets,
-                                   const unsigned int packet_length,
-                                   const unsigned int timeout,
+                                   size_t length,
+                                   unsigned int packets,
+                                   unsigned int packet_length,
+                                   unsigned int timeout,
                                    const UsbTransferCallback& callback) = 0;
 
  protected: