Report polymorphism in BuiltinFunctions.IterNode.

Author: fangerer

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/BuiltinFunctions.java

@@ -1291,6 +1291,7 @@ private Object[] getArray(PTuple tuple) {
     // iter(object[, sentinel])
     @Builtin(name = ITER, minNumOfPositionalArgs = 1, maxNumOfPositionalArgs = 2)
     @GenerateNodeFactory
+    @ReportPolymorphism
     public abstract static class IterNode extends PythonBinaryBuiltinNode {
         @Specialization(guards = "isNoValue(sentinel)", limit = "getCallSiteInlineCacheMaxDepth()")
         static Object iter(VirtualFrame frame, Object object, @SuppressWarnings("unused") PNone sentinel,