Use interface associations to check function permissions.

device/usb/usb_device_handle.h

 // 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.
 
 #ifndef DEVICE_USB_USB_DEVICE_HANDLE_H_
 #define DEVICE_USB_USB_DEVICE_HANDLE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 93 matching lines @@
       unsigned int timeout,
       const IsochronousTransferCallback& callback) = 0;
 
   virtual void GenericTransfer(UsbEndpointDirection direction,
                                uint8_t endpoint_number,
                                scoped_refptr<net::IOBuffer> buffer,
                                size_t length,
                                unsigned int timeout,
                                const TransferCallback& callback) = 0;
 
-  // Gets the interface containing |endpoint_address|. Returns false if no
+  // Gets the interface containing |endpoint_address|. Returns nullptr if no
   // claimed interface contains that endpoint.
-  virtual bool FindInterfaceByEndpoint(uint8_t endpoint_address,
-                                       uint8_t* interface_number) = 0;
+  virtual const UsbInterfaceDescriptor* FindInterfaceByEndpoint(
+      uint8_t endpoint_address) = 0;
 
  protected:
   friend class base::RefCountedThreadSafe<UsbDeviceHandle>;
 
   UsbDeviceHandle();
 
   virtual ~UsbDeviceHandle();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(UsbDeviceHandle);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_USB_USB_DEVICE_HANDLE_H_