Tweak the documentation of "fullscreen element ready check"

Source/core/dom/FullscreenElementStack.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
@@ skipping 153 matching lines @@
 {
     // NOTE: the context dispose phase is not supported in oilpan. Please
     // consider using the detach phase instead.
     m_fullScreenElement = nullptr;
     m_fullScreenElementStack.clear();
 }
 #endif
 
 bool FullscreenElementStack::elementReady(Element& element, RequestType requestType)
 {
-    // A fullscreen element ready check for an element returns true if all of the following are
-    // true, and false otherwise:
+    // A fullscreen element ready check for an element |element| returns true if all of the
+    // following are true, and false otherwise:
 
-    // element is in a document.
+    // |element| is in a document.
     if (!element.inDocument())
         return false;
 
-    // element's node document's fullscreen enabled flag is set.
+    // |element|'s node document's fullscreen enabled flag is set.
     if (!fullscreenIsAllowedForAllOwners(element.document())) {
         if (requestType == PrefixedVideoRequest)
             UseCounter::count(element.document(), UseCounter::VideoFullscreenAllowedExemption);
         else
             return false;
     }
 
-    // element's node document's fullscreen element stack is either empty or its top element is an
-    // ancestor of element.
+    // |element|'s node document's fullscreen element stack is either empty or its top element is an
+    // ancestor of |element|.
     if (Element* topElement = fullscreenElementFrom(element.document())) {
         if (!element.isDescendantOf(topElement))
             return false;
     }
 
-    // element has no ancestor element whose local name is iframe and namespace is the HTML
+    // |element| has no ancestor element whose local name is iframe and namespace is the HTML
     // namespace.
     if (Traversal<HTMLIFrameElement>::firstAncestor(element))
         return false;
 
     return true;
 }
 
 void FullscreenElementStack::requestFullscreen(Element& element, RequestType requestType)
 {
     // Ignore this request if the document is not in a live frame.
@@ skipping 395 matching lines @@
 void FullscreenElementStack::trace(Visitor* visitor)
 {
     visitor->trace(m_fullScreenElement);
     visitor->trace(m_fullScreenElementStack);
     visitor->trace(m_fullScreenRenderer);
     visitor->trace(m_eventQueue);
     DocumentSupplement::trace(visitor);
 }
 
 } // namespace blink