Have Document::topDocument() return a reference

Source/core/accessibility/AXObjectCache.cpp

 /*
  * Copyright (C) 2008, 2009, 2010 Apple 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
@@ skipping 89 matching lines @@
 }
 
 void AXComputedObjectAttributeCache::clear()
 {
     m_idMapping.clear();
 }
 
 bool AXObjectCache::gAccessibilityEnabled = false;
 bool AXObjectCache::gInlineTextBoxAccessibility = false;
 
-AXObjectCache::AXObjectCache(const Document* doc)
-    : m_notificationPostTimer(this, &AXObjectCache::notificationPostTimerFired)
+AXObjectCache::AXObjectCache(Document& document)
+    : m_document(document)
+    , m_notificationPostTimer(this, &AXObjectCache::notificationPostTimerFired)
 {
-    m_document = const_cast<Document*>(doc);

[adamk, 2014/02/26 17:30:52]

Ha! Thanks for getting rid of this const_cast

     m_computedObjectAttributeCache = AXComputedObjectAttributeCache::create();
 }
 
 AXObjectCache::~AXObjectCache()
 {
     m_notificationPostTimer.stop();
 
     HashMap<AXID, RefPtr<AXObject> >::iterator end = m_objects.end();
     for (HashMap<AXID, RefPtr<AXObject> >::iterator it = m_objects.begin(); it != end; ++it) {
         AXObject* obj = (*it).value.get();
@@ skipping 316 matching lines @@
     newObj->setLastKnownIsIgnoredValue(newObj->accessibilityIsIgnored());
 
     return newObj.get();
 }
 
 AXObject* AXObjectCache::rootObject()
 {
     if (!gAccessibilityEnabled)
         return 0;
 
-    return getOrCreate(m_document->view());
+    return getOrCreate(m_document.view());
 }
 
 AXObject* AXObjectCache::getOrCreate(AccessibilityRole role)
 {
     RefPtr<AXObject> obj = nullptr;
 
     // will be filled in...
     switch (role) {
     case ListBoxOptionRole:
         obj = AXListBoxOption::create();
@@ skipping 573 matching lines @@
 {
     postPlatformNotification(getOrCreate(scrollView), AXScrollPositionChanged);
 }
 
 void AXObjectCache::handleScrollPositionChanged(RenderObject* renderObject)
 {
     postPlatformNotification(getOrCreate(renderObject), AXScrollPositionChanged);
 }
 
 } // namespace WebCore