Aria disabled does not apply to descendant elements

Source/modules/accessibility/AXObject.cpp

Index: Source/modules/accessibility/AXObject.cpp
diff --git a/Source/modules/accessibility/AXObject.cpp b/Source/modules/accessibility/AXObject.cpp
index f5cd5277653bcf7d39b8ee6be823cef3b425d883..80c8b6d82d2d1dbf038b5d045d512e36dd5801bb 100644
--- a/Source/modules/accessibility/AXObject.cpp
+++ b/Source/modules/accessibility/AXObject.cpp
@@ -368,6 +368,7 @@ void AXObject::updateCachedAttributeValuesIfNeeded() const
     m_lastModificationCount = cache->modificationCount();
     m_cachedIsInertOrAriaHidden = computeIsInertOrAriaHidden();
     m_cachedIsDescendantOfBarrenParent = computeIsDescendantOfBarrenParent();
+    m_cachedIsDescendantOfDisabledParent = computeIsDescendantOfDisabledParent();
     m_cachedIsIgnored = computeAccessibilityIsIgnored();
     m_cachedLiveRegionRoot = isLiveRegion() ?
         this :
@@ -434,6 +435,24 @@ bool AXObject::computeIsDescendantOfBarrenParent() const
     return false;
 }
 
+bool AXObject::isDescendantOfDisabledParent() const
+{
+    updateCachedAttributeValuesIfNeeded();
+    return m_cachedIsDescendantOfDisabledParent;
+}
+
+bool AXObject::computeIsDescendantOfDisabledParent() const

[dmazzoni, 2015/03/23 16:16:51]

Please rewrite this to look more like computeIsInertOrAriaHidden instead.

Right now for every element on the page you're walking up all the parents to see
if it's disabled - but a faster way to do this is to check the current element,
then check the parent by calling isDescendantOfDisabledParent - then if the
parent was already computed you don't have to repeat that work.

computeIsDescendantOfBarrenParent could probably be improved too, but we don't
have to do it in this change.

+{
+    for (AXObject* parent = const_cast<AXObject*>(this); parent; parent = parent->parentObject()) {

[dmazzoni, 2015/03/23 16:16:51]

Why do you need the const_cast? Can you write it as:

    for (const AXObject* parent = this; ...

?

If not, that's okay, but try it that way first.

+        const AtomicString& disabled = parent->getAttribute(aria_disabledAttr);
+        if (equalIgnoringCase(disabled, "true"))
+            return true;
+        if (equalIgnoringCase(disabled, "false"))
+            return false;
+    }
+    return false;
+}
+
 bool AXObject::lastKnownIsIgnoredValue()
 {
     if (m_lastKnownIsIgnoredValue == DefaultBehavior)