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;
+
 /*main:[null]*/
-main() {}
+main() {
+  zero();
+  one();
+  half();
+  large();

[Siggi Cherem (dart-lang), 2017/08/28 22:34:57]

maybe add something that doesn't fit in 32 bit as well?

[Johnni Winther, 2017/08/29 08:31:25]

Done.

+}