Bug 147755 nsIAccessible's accName returns empty string instead of picking up label for XUL listbox node

r=aaronl, sr=bzbarsky
extract accName by calling GetXULAccName()

accessible/src/xul/nsXULColorPickerAccessible.cpp

@@ -93,8 +93,7 @@ NS_IMETHODIMP nsXULColorPickerTileAccessible::GetAccState(PRUint32 *_retval)
 
 NS_IMETHODIMP nsXULColorPickerTileAccessible::GetAccName(nsAString& _retval)
 {
-  _retval.Assign(NS_LITERAL_STRING(""));
-  return NS_OK;
+  return GetXULAccName(_retval);
 }
 
 NS_IMETHODIMP nsXULColorPickerTileAccessible::GetAccValue(nsAString& _retval)

accessible/src/xul/nsXULSelectAccessible.cpp

@@ -80,6 +80,11 @@ nsAccessible(aDOMNode, aShell)
 {
 }
 
+NS_IMETHODIMP nsXULSelectableAccessible::GetAccName(nsAString& _retval)
+{
+  return GetXULAccName(_retval);
+}
+
 NS_IMPL_ISUPPORTS_INHERITED1(nsXULSelectableAccessible, nsAccessible, nsIAccessibleSelectable)
 
 NS_IMETHODIMP nsXULSelectableAccessible::ChangeSelection(PRInt32 aIndex, PRUint8 aMethod, PRBool *aSelState)

accessible/src/xul/nsXULSelectAccessible.h

@@ -84,6 +84,8 @@ public:
   nsXULSelectableAccessible(nsIDOMNode* aDOMNode, nsIWeakReference* aShell);
   virtual ~nsXULSelectableAccessible() {}
 
+  NS_IMETHOD GetAccName(nsAString& _retval);
+
 protected:
   NS_IMETHOD ChangeSelection(PRInt32 aIndex, PRUint8 aMethod, PRBool *aSelState);
 };