implement kernel -> ssa for literals

tests/compiler/dart2js/kernel/simple_function_test.dart

Index: tests/compiler/dart2js/kernel/simple_function_test.dart
diff --git a/tests/compiler/dart2js/kernel/simple_function_test.dart b/tests/compiler/dart2js/kernel/simple_function_test.dart
index 9daf5e3e37049d72369de07b9e6294df8ff6b002..c252716fc281a7a4372bb35e4824b54550f35465 100644
--- a/tests/compiler/dart2js/kernel/simple_function_test.dart
+++ b/tests/compiler/dart2js/kernel/simple_function_test.dart
@@ -3,7 +3,29 @@ import 'package:test/test.dart';
 import 'helper.dart' show check;
 
 main() {
-  test('compile function that returns a constant', () {
-    return check("main() { return 1; }");
+  group('compile function that returns a value', () {
+    test('constant int', () {
+      return check("main() { return 1; }");
+    });
+
+    test('constant double', () {
+      return check("main() { return 1.0; }");
+    });
+
+    test('constant string', () {
+      return check("main() { return 'hello'; }");
+    });
+
+    test('constant bool', () {
+      return check("main() { return true; }");
+    });
+
+    test('constant symbol', () {
+      return check("main() { return #hello; }");
+    });
+
+    test('null', () {
+      return check("main() { return null; }");
+    });
   });
 }