Handle int/double literals in inference

tests/compiler/dart2js/inference/data/simple.dart

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+/*zero:[exact=JSUInt31]*/
+zero() => 0;
+
+/*one:[exact=JSUInt31]*/
+one() => 1;
+
+/*half:[exact=JSDouble]*/
+half() => 0.5;
+
+/*large:[subclass=JSUInt32]*/
+large() => 2147483648;
+
+/*huge:[subclass=JSPositiveInt]*/
+huge() => 4294967296;
+
 /*main:[null]*/
-main() {}
+main() {
+  zero();
+  one();
+  half();
+  large();
+  huge();
+}