Bug 1175182 - Expose fractions and roots as ATK_ROLE_PANEL for ATK < 2.16. r=surkov

--HG--
extra : rebase_source : 5292ec1c6f415a627f9507aff3b8deb4797341dd

accessible/atk/AccessibleWrap.cpp

@@ -688,7 +688,7 @@ getRoleCB(AtkObject *aAtkObj)
     aAtkObj->role = ATK_ROLE_TEXT;
   else if ((aAtkObj->role == ATK_ROLE_MATH_FRACTION ||
             aAtkObj->role == ATK_ROLE_MATH_ROOT) && !IsAtkVersionAtLeast(2, 16))
-    aAtkObj->role = ATK_ROLE_UNKNOWN;
+    aAtkObj->role = ATK_ROLE_SECTION;
 
   return aAtkObj->role;
 }