Use a new Supplement constructor for (Worker)Navigator supplements

third_party/WebKit/Source/modules/gamepad/NavigatorGamepad.cpp

 /*
  * Copyright (C) 2011, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 64 matching lines @@
   if (!document.frame() || !document.frame()->domWindow())
     return 0;
   Navigator& navigator = *document.frame()->domWindow()->navigator();
   return &from(navigator);
 }
 
 NavigatorGamepad& NavigatorGamepad::from(Navigator& navigator) {
   NavigatorGamepad* supplement = static_cast<NavigatorGamepad*>(
       Supplement<Navigator>::from(navigator, supplementName()));
   if (!supplement) {
-    supplement = new NavigatorGamepad(navigator.frame());
+    supplement = new NavigatorGamepad(navigator);
     provideTo(navigator, supplementName(), supplement);
   }
   return *supplement;
 }
 
 GamepadList* NavigatorGamepad::getGamepads(Navigator& navigator) {
   return NavigatorGamepad::from(navigator).gamepads();
 }
 
 GamepadList* NavigatorGamepad::gamepads() {
@@ skipping 63 matching lines @@
   const AtomicString& eventName = gamepad->connected()
                                       ? EventTypeNames::gamepadconnected
                                       : EventTypeNames::gamepaddisconnected;
   document->frame()->domWindow()->dispatchEvent(
       GamepadEvent::create(eventName, false, true, gamepad));
 
   if (!m_pendingEvents.isEmpty())
     m_dispatchOneEventRunner->runAsync();
 }
 
-NavigatorGamepad::NavigatorGamepad(LocalFrame* frame)
-    : ContextLifecycleObserver(frame->document()),
-      PlatformEventController(frame ? frame->page() : 0),
+NavigatorGamepad::NavigatorGamepad(Navigator& navigator)
+    : Supplement<Navigator>(navigator),
+      ContextLifecycleObserver(navigator.frame()->document()),

[sof, 2017/01/23 08:05:31]

ftr, crbug.com/683520 suggests that there's a missing null check on
navigator.frame() in this area. 

(The unconditional use of navigator.frame() is in conflict with the conditional
use on the line below.)

+      PlatformEventController(navigator.frame() ? navigator.frame()->page()
+                                                : 0),
       m_dispatchOneEventRunner(AsyncMethodRunner<NavigatorGamepad>::create(
           this,
           &NavigatorGamepad::dispatchOneEvent)) {
-  if (frame)
-    frame->domWindow()->registerEventListenerObserver(this);
+  if (navigator.frame())
+    navigator.frame()->domWindow()->registerEventListenerObserver(this);
 }
 
 NavigatorGamepad::~NavigatorGamepad() {}
 
 const char* NavigatorGamepad::supplementName() {
   return "NavigatorGamepad";
 }
 
 void NavigatorGamepad::contextDestroyed(ExecutionContext*) {
   stopUpdating();
@@ skipping 79 matching lines @@
     if (connectedGamepadChanged || (!oldWasConnected && newIsConnected)) {
       m_pendingEvents.append(newGamepad);
     }
   }
 
   if (!m_pendingEvents.isEmpty())
     m_dispatchOneEventRunner->runAsync();
 }
 
 }  // namespace blink