Introducing chrome.usb.getDevices/openDevice API

chrome/browser/usb/usb_service.h

 // Copyright (c) 2012 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 CHROME_BROWSER_USB_USB_SERVICE_H_
 #define CHROME_BROWSER_USB_USB_SERVICE_H_
 
 #include <map>
 #include <utility>
 #include <vector>
@@ skipping 27 matching lines @@
   // |vendor_id| and |product_id|, inserting them into |devices|. Clears
   // |devices| before use. Calls |callback| once |devices| is populated.
   // The result will be sorted by id in increasing order. Must be called on
   // FILE thread.
   void FindDevices(
       const uint16 vendor_id,
       const uint16 product_id,
       int interface_id,
       const base::Callback<void(ScopedDeviceVector vector)>& callback);
 
+
+  scoped_refptr<UsbDevice> GetDeviceById(uint32 unique_id);
+
   // Get all of the devices attached to the system, inserting them into
   // |devices|. Clears |devices| before use. The result will be sorted by id
   // in increasing order. Must be called on FILE thread.
   void GetDevices(std::vector<scoped_refptr<UsbDevice> >* devices);
 
  private:
   friend struct DefaultSingletonTraits<UsbService>;
   friend class base::DeleteHelper<UsbService>;
 
   UsbService();
@@ skipping 21 matching lines @@
       const uint16 vendor_id,
       const uint16 product_id,
       const base::Callback<void(ScopedDeviceVector vector)>& callback,
       bool success);
 
   // Enumerate USB devices from OS and Update devices_ map.
   void RefreshDevices();
 
   scoped_refptr<UsbContext> context_;
 
+  uint32 next_unique_id_;
+
   // The map from PlatformUsbDevices to UsbDevices.
   typedef std::map<PlatformUsbDevice, scoped_refptr<UsbDevice> > DeviceMap;
   DeviceMap devices_;
 
   DISALLOW_COPY_AND_ASSIGN(UsbService);
 };
 
 #endif  // CHROME_BROWSER_USB_USB_SERVICE_H_