Implement aria properties setsize and posinset.

Source/modules/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:
  *
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@@ skipping 701 matching lines @@
 
 bool AXObject::supportsRangeValue() const
 {
     return isProgressIndicator()
         || isMeter()
         || isSlider()
         || isScrollbar()
         || isSpinButton();
 }
 
+bool AXObject::supportssetSizePosInSet() const
+{
+    if (parentObject() && ((roleValue() == ListBoxOptionRole && parentObject()->roleValue() == ListBoxRole)

[shreeramk, 2015/04/09 13:50:15]

I'd like your feedback on this check condition.

[dmazzoni, 2015/04/09 15:19:20]

This looks right, but it should also apply to ListItemRole with a parent of
ListRole, and TreeItemRole with a parent of TreeRole or TreeItemRole (tree items
can be nested).

Oh, and also MenuListOptionRole with a a parent of MenuListRole.

I think that's all, but you can check the ARIA spec for aria-posinset and you
can look over the list of roles to see if any others look like list-like roles.

I'd write it using a few more lines of code to make it more readable, something
like:

AXObject* parent = parentObject();
if (!parent)
    return false;

int role = roleValue();
int parentRole = parent->roleValue();

if ((role == ListItemRole && parentRole == ListRole)
    || (role == ListBoxOptionRole && parentRole == ListBoxRole)
...

+        || (roleValue() == ListItemRole && parentObject()->roleValue() == ListRole)
+        || (roleValue() == RadioButtonRole && parentObject()->roleValue() == RadioGroupRole)
+        || (roleValue() == TabRole && parentObject()->roleValue() == TabListRole)))
+            return true;
+
+    return false;
+}
+
 void AXObject::ariaTreeRows(AccessibilityChildrenVector& result)
 {
     for (const auto& child : children()) {
         // Add tree items as the rows.
         if (child->roleValue() == TreeItemRole)
             result.append(child);
 
         // Now see if this item also has rows hiding inside of it.
         child->ariaTreeRows(result);
     }
@@ skipping 568 matching lines @@
 }
 
 const AtomicString& AXObject::internalRoleName(AccessibilityRole role)
 {
     static const Vector<AtomicString>* internalRoleNameVector = createInternalRoleNameVector();
 
     return internalRoleNameVector->at(role);
 }
 
 } // namespace blink