Make int and double nullable by default

test/dart_codegen/expect/core/iterable.dart

Index: test/dart_codegen/expect/core/iterable.dart
diff --git a/test/dart_codegen/expect/core/iterable.dart b/test/dart_codegen/expect/core/iterable.dart
index ef8f04dfc62e5193935a78301cad7bc3d96ba27e..072f79109dd10e9f86cd318536eb8fcf7a9e6a96 100644
--- a/test/dart_codegen/expect/core/iterable.dart
+++ b/test/dart_codegen/expect/core/iterable.dart
@@ -46,9 +46,9 @@ part of dart.core;
  class _GeneratorIterable<E> extends IterableBase<E> implements EfficientLength {final int _start;
  final int _end;
  final _Generator<E> _generator;
- _GeneratorIterable(this._end, E generator(int n)) : _start = 0, _generator = ((__x11) => DDC$RT.cast(__x11, dynamic, DDC$RT.type((__t9<E> _) {
+ _GeneratorIterable(this._end, E generator(int n)) : _start = 0, _generator = ((__x10) => DDC$RT.cast(__x10, dynamic, DDC$RT.type((__t8<E> _) {
 }
-), "CastGeneral", """line 319, column 22 of dart:core/iterable.dart: """, __x11 is __t9<E>, false))((generator != null) ? generator : _id);
+), "CastGeneral", """line 319, column 22 of dart:core/iterable.dart: """, __x10 is __t8<E>, false))((generator != null) ? generator : _id);
  _GeneratorIterable.slice(this._start, this._end, this._generator);
  Iterator<E> get iterator => new _GeneratorIterator<E>(_start, _end, _generator);
  int get length => _end - _start;
@@ -80,7 +80,7 @@ _current = _generator(_index);
  return true;
 }
  else {
-_current = ((__x12) => DDC$RT.cast(__x12, Null, E, "CastLiteral", """line 360, column 18 of dart:core/iterable.dart: """, __x12 is E, false))(null);
+_current = null;
  return false;
 }
 }
@@ -88,4 +88,4 @@ _current = ((__x12) => DDC$RT.cast(__x12, Null, E, "CastLiteral", """line 360, c
 }
  abstract class BidirectionalIterator<E> implements Iterator<E> {bool movePrevious();
 }
- typedef E __t9<E>(int __u10);
+ typedef E __t8<E>(int __u9);