Remove the fullScreenEnabled setting

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 182 matching lines @@
 
         // This algorithm is not allowed to show a pop-up:
         //   An algorithm is allowed to show a pop-up if, in the task in which the algorithm is running, either:
         //   - an activation behavior is currently being processed whose click event was trusted, or
         //   - the event listener for a trusted click event is being handled.
         // FIXME: Does this need to null-check settings()?
         if (!UserGestureIndicator::processingUserGesture() && (!isHTMLMediaElement(*element) || document()->settings()->mediaFullscreenRequiresUserGesture()))
             break;
 
         // There is a previously-established user preference, security risk, or platform limitation.
-        if (!document()->settings() || !document()->settings()->fullScreenEnabled())
-            break;
 
         // 2. Let doc be element's node document. (i.e. "this")
         Document* currentDoc = document();
 
         // 3. Let docs be all doc's ancestor browsing context's documents (if any) and doc.
         Deque<Document*> docs;
 
         do {
             docs.prepend(currentDoc);
             currentDoc = currentDoc->ownerElement() ? &currentDoc->ownerElement()->document() : 0;
@@ skipping 152 matching lines @@
     // Top-level browsing contexts are implied to have their allowFullScreen attribute set.
     return fullscreenIsAllowedForAllOwners(document);
 }
 
 void FullscreenElementStack::webkitWillEnterFullScreenForElement(Element* element)
 {
     ASSERT(element);
     if (!document()->isActive())
         return;
 
-    ASSERT(document()->settings()); // If we're active we must have settings.
-    ASSERT(document()->settings()->fullScreenEnabled());
-
     if (m_fullScreenRenderer)
         m_fullScreenRenderer->unwrapRenderer();
 
     m_fullScreenElement = element;
 
     // Create a placeholder block for a the full-screen element, to keep the page from reflowing
     // when the element is removed from the normal flow. Only do this for a RenderBox, as only
     // a box will have a frameRect. The placeholder will be created in setFullScreenRenderer()
     // during layout.
     RenderObject* renderer = m_fullScreenElement->renderer();
@@ skipping 186 matching lines @@
         if (!target)
             target = fullscreen->webkitCurrentFullScreenElement();
     }
 
     if (!target)
         target = doc;
     m_fullScreenChangeEventTargetQueue.append(target);
 }
 
 } // namespace WebCore