Change UsbDeviceFilter to use const references instead of

chrome/browser/chromeos/printer_detector/cups_printer_detector.cc

Index: chrome/browser/chromeos/printer_detector/cups_printer_detector.cc
diff --git a/chrome/browser/chromeos/printer_detector/cups_printer_detector.cc b/chrome/browser/chromeos/printer_detector/cups_printer_detector.cc
index 3719c474e7dbffc25c9f6fb68d920cd25842f675..05369a7ae9c694b9f9b8120248c46638bfd17a00 100644
--- a/chrome/browser/chromeos/printer_detector/cups_printer_detector.cc
+++ b/chrome/browser/chromeos/printer_detector/cups_printer_detector.cc
@@ -102,7 +102,7 @@ class CupsPrinterDetectorImpl : public PrinterDetector,
   // UsbService::observer override.
   void OnDeviceRemoved(scoped_refptr<device::UsbDevice> device) override {
     DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    if (!UsbDeviceIsPrinter(device)) {
+    if (!UsbDeviceIsPrinter(*device)) {
       return;
     }
     known_printers_.erase(device->guid());
@@ -132,7 +132,7 @@ class CupsPrinterDetectorImpl : public PrinterDetector,
                         bool hotplugged) {
     DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
-    if (!UsbDeviceIsPrinter(device) ||
+    if (!UsbDeviceIsPrinter(*device) ||
         base::ContainsKey(known_printers_, device->guid())) {
       return;
     }