Implement aria properties setsize and posinset.

Source/modules/accessibility/AXNodeObject.cpp

Index: Source/modules/accessibility/AXNodeObject.cpp
diff --git a/Source/modules/accessibility/AXNodeObject.cpp b/Source/modules/accessibility/AXNodeObject.cpp
index c9294b0ff1f2039b98b16582f4c5c83e50ccc39a..4afa9437c5a1d178082ad7ecfcb428b54b85e78a 100644
--- a/Source/modules/accessibility/AXNodeObject.cpp
+++ b/Source/modules/accessibility/AXNodeObject.cpp
@@ -1172,6 +1172,28 @@ InvalidState AXNodeObject::invalidState() const
     return InvalidStateUndefined;
 }
 
+int AXNodeObject::posInSet() const
+{
+    if (supportssetSizePosInSet()) {

[dmazzoni, 2015/04/09 15:15:37]

nit: how about supportsSetSizeAndPosInSet

+        if (hasAttribute(aria_posinsetAttr))
+            return getAttribute(aria_posinsetAttr).toInt();
+        return node()->nodeIndex();

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

And this to get index?

Is this correct API to get child's index in parent?

[dmazzoni, 2015/04/09 15:15:37]

Yes

+    }
+
+    return 0;
+}
+
+int AXNodeObject::setSize() const
+{
+    if (supportssetSizePosInSet()) {
+        if (hasAttribute(aria_setsizeAttr))
+            return getAttribute(aria_setsizeAttr).toInt();
+        return node()->parentNode()->countChildren();

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

Is this correct API to get the child count of parent?

[dmazzoni, 2015/04/09 15:15:37]

Yes, but please check that parentNode() is not null just in case

+    }
+
+    return 0;
+}
+
 String AXNodeObject::ariaInvalidValue() const
 {
     if (invalidState() == InvalidStateOther)