Use a new Supplement constructor in Navigator supplements (part 2)

third_party/WebKit/Source/modules/webusb/NavigatorUSB.cpp

 // Copyright 2015 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.
 
 #include "modules/webusb/NavigatorUSB.h"
 
 #include "core/frame/Navigator.h"
 #include "modules/webusb/USB.h"
 
 namespace blink {
@@ skipping 14 matching lines @@
 
 USB* NavigatorUSB::usb() {
   return m_usb;
 }
 
 DEFINE_TRACE(NavigatorUSB) {
   visitor->trace(m_usb);
   Supplement<Navigator>::trace(visitor);
 }
 
-NavigatorUSB::NavigatorUSB(Navigator& navigator) {
+NavigatorUSB::NavigatorUSB(Navigator& navigator)
+    : Supplement<Navigator>(navigator) {
   if (navigator.frame())
     m_usb = USB::create(*navigator.frame());
 }
 
 const char* NavigatorUSB::supplementName() {
   return "NavigatorUSB";
 }
 
 }  // namespace blink