Add live region root to the cached properties of an AXObject.

Source/core/accessibility/AXObject.cpp

 /*
  * Copyright (C) 2008, 2009, 2011 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 118 matching lines @@
 }
 
 AXObject::AXObject()
     : m_id(0)
     , m_haveChildren(false)
     , m_role(UnknownRole)
     , m_lastKnownIsIgnoredValue(DefaultBehavior)
     , m_detached(false)
     , m_lastModificationCount(-1)
     , m_cachedIsIgnored(false)
+    , m_cachedLiveRegionRoot(0)
 {
 }
 
 AXObject::~AXObject()
 {
     ASSERT(isDetached());
 }
 
 void AXObject::detach()
 {
@@ skipping 107 matching lines @@
 
 void AXObject::updateCachedAttributeValuesIfNeeded() const
 {
     AXObjectCacheImpl* cache = axObjectCache();
     if (!cache)
         return;
 
     if (cache->modificationCount() == m_lastModificationCount)
         return;
 
+    m_lastModificationCount = cache->modificationCount();
     m_cachedIsIgnored = computeAccessibilityIsIgnored();
-    m_lastModificationCount = cache->modificationCount();
+    m_cachedLiveRegionRoot = isLiveRegion() ? this : (parentObjectIfExists() ? parentObjectIfExists()->liveRegionRoot() : 0);

[aboxhall, 2014/10/27 17:29:53]

I'd consider wrapping this onto a few lines to make the logic clearer.

[dmazzoni, 2014/10/27 18:08:25]

Done.

 }
 
 bool AXObject::accessibilityIsIgnoredByDefault() const
 {
     return defaultObjectInclusion() == IgnoreObject;
 }
 
 AXObjectInclusion AXObject::accessibilityPlatformIncludesObject() const
 {
     if (isMenuListPopup() || isMenuListOption())
@@ skipping 107 matching lines @@
     return equalIgnoringCase(getAttribute(aria_multilineAttr), "true");
 }
 
 bool AXObject::ariaPressedIsPresent() const
 {
     return !getAttribute(aria_pressedAttr).isEmpty();
 }
 
 bool AXObject::supportsARIAAttributes() const
 {
-    return supportsARIALiveRegion()
+    return isLiveRegion()
         || supportsARIADragging()
         || supportsARIADropping()
         || supportsARIAFlowTo()
         || supportsARIAOwns()
         || hasAttribute(aria_labelAttr);
 }
 
 bool AXObject::supportsRangeValue() const
 {
     return isProgressIndicator()
@@ skipping 11 matching lines @@
 
         // Add tree items as the rows.
         if (obj->roleValue() == TreeItemRole)
             result.append(obj);
 
         // Now see if this item also has rows hiding inside of it.
         obj->ariaTreeRows(result);
     }
 }
 
-bool AXObject::supportsARIALiveRegion() const
+bool AXObject::isLiveRegion() const
 {
-    const AtomicString& liveRegion = ariaLiveRegionStatus();
+    const AtomicString& liveRegion = liveRegionStatus();
     return equalIgnoringCase(liveRegion, "polite") || equalIgnoringCase(liveRegion, "assertive");
 }
 
+const AXObject* AXObject::liveRegionRoot() const
+{
+    updateCachedAttributeValuesIfNeeded();
+    return m_cachedLiveRegionRoot;
+}
+
+const AtomicString& AXObject::containerLiveRegionStatus() const
+{
+    updateCachedAttributeValuesIfNeeded();
+    return m_cachedLiveRegionRoot ? m_cachedLiveRegionRoot->liveRegionStatus() : nullAtom;
+}
+
+const AtomicString& AXObject::containerLiveRegionRelevant() const
+{
+    updateCachedAttributeValuesIfNeeded();
+    return m_cachedLiveRegionRoot ? m_cachedLiveRegionRoot->liveRegionRelevant() : nullAtom;
+}
+
+bool AXObject::containerLiveRegionAtomic() const
+{
+    updateCachedAttributeValuesIfNeeded();
+    return m_cachedLiveRegionRoot ? m_cachedLiveRegionRoot->liveRegionAtomic() : false;
+}
+
+bool AXObject::containerLiveRegionBusy() const
+{
+    updateCachedAttributeValuesIfNeeded();
+    return m_cachedLiveRegionRoot ? m_cachedLiveRegionRoot->liveRegionBusy() : false;
+}
+
 void AXObject::markCachedElementRectDirty() const
 {
     for (unsigned i = 0; i < m_children.size(); ++i)
         m_children[i].get()->markCachedElementRectDirty();
 }
 
 IntPoint AXObject::clickPoint()
 {
     LayoutRect rect = elementRect();
     return roundedIntPoint(LayoutPoint(rect.x() + rect.width() / 2, rect.y() + rect.height() / 2));
@@ skipping 467 matching lines @@
         return ToggleButtonRole;
     if (ariaHasPopup())
         return PopUpButtonRole;
     // We don't contemplate RadioButtonRole, as it depends on the input
     // type.
 
     return ButtonRole;
 }
 
 } // namespace blink