Remove DartString from constants.

tests/compiler/dart2js/metadata_test.dart

 // Copyright (c) 2012, 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.
 
 import 'package:async_helper/async_helper.dart';
 import 'package:compiler/src/constants/values.dart' show PrimitiveConstantValue;
 import 'package:expect/expect.dart';
 import 'compiler_helper.dart';
 import 'package:compiler/src/parser/partial_elements.dart'
     show PartialMetadataAnnotation;
@@ skipping 23 matching lines @@
                    main() {}""";
 
   analyzeAndCheck(source1, name, (compiler, element) {
     compiler.enqueuer.resolution.queueIsClosed = false;
     Expect.equals(
         1, element.metadata.length, 'Unexpected metadata count on $element.');
     PartialMetadataAnnotation annotation = element.metadata.first;
     annotation.ensureResolved(compiler.resolution);
     PrimitiveConstantValue value =
         compiler.constants.getConstantValue(annotation.constant);
-    Expect.stringEquals('xyz', value.primitiveValue.slowToString());
+    Expect.stringEquals('xyz', value.primitiveValue);
 
     checkPosition(
         annotation, annotation.cachedNode, source1, compiler.reporter);
   });
 
   // Ensure that each repeated annotation has a unique instance of
   // [MetadataAnnotation].
   var source2 = """const native = 'xyz';
                    @native @native
                    $declaration
                    main() {}""";
 
   analyzeAndCheck(source2, name, (compiler, element) {
     compiler.enqueuer.resolution.queueIsClosed = false;
     Expect.equals(2, element.metadata.length);
     PartialMetadataAnnotation annotation1 = element.metadata.elementAt(0);
     PartialMetadataAnnotation annotation2 = element.metadata.elementAt(1);
     annotation1.ensureResolved(compiler.resolution);
     annotation2.ensureResolved(compiler.resolution);
     Expect.isFalse(
         identical(annotation1, annotation2), 'expected unique instances');
     Expect.notEquals(annotation1, annotation2, 'expected unequal instances');
     PrimitiveConstantValue value1 =
         compiler.constants.getConstantValue(annotation1.constant);
     PrimitiveConstantValue value2 =
         compiler.constants.getConstantValue(annotation2.constant);
     Expect.identical(value1, value2, 'expected same compile-time constant');
-    Expect.stringEquals('xyz', value1.primitiveValue.slowToString());
-    Expect.stringEquals('xyz', value2.primitiveValue.slowToString());
+    Expect.stringEquals('xyz', value1.primitiveValue);
+    Expect.stringEquals('xyz', value2.primitiveValue);
 
     checkPosition(
         annotation1, annotation1.cachedNode, source2, compiler.reporter);
     checkPosition(
         annotation2, annotation2.cachedNode, source2, compiler.reporter);
   });
 
   if (isTopLevelOnly) return;
 
   // Ensure that a compile-time constant can be resolved from an
   // annotation.
   var source3 = """const native = 'xyz';
                    class Foo {
                      @native
                      $declaration
                    }
                    main() {}""";
 
   analyzeAndCheck(source3, 'Foo', (compiler, element) {
     compiler.enqueuer.resolution.queueIsClosed = false;
     Expect.equals(0, element.metadata.length);
     element.ensureResolved(compiler.resolution);
     Expect.equals(0, element.metadata.length);
     element = element.lookupLocalMember(name);
     Expect.equals(1, element.metadata.length);
     PartialMetadataAnnotation annotation = element.metadata.first;
     annotation.ensureResolved(compiler.resolution);
     PrimitiveConstantValue value =
         compiler.constants.getConstantValue(annotation.constant);
-    Expect.stringEquals('xyz', value.primitiveValue.slowToString());
+    Expect.stringEquals('xyz', value.primitiveValue);
 
     checkPosition(
         annotation, annotation.cachedNode, source3, compiler.reporter);
   });
 
   // Ensure that each repeated annotation has a unique instance of
   // [MetadataAnnotation].
   var source4 = """const native = 'xyz';
                    class Foo {
                      @native @native
@@ skipping 13 matching lines @@
     annotation1.ensureResolved(compiler.resolution);
     annotation2.ensureResolved(compiler.resolution);
     Expect.isFalse(
         identical(annotation1, annotation2), 'expected unique instances');
     Expect.notEquals(annotation1, annotation2, 'expected unequal instances');
     PrimitiveConstantValue value1 =
         compiler.constants.getConstantValue(annotation1.constant);
     PrimitiveConstantValue value2 =
         compiler.constants.getConstantValue(annotation2.constant);
     Expect.identical(value1, value2, 'expected same compile-time constant');
-    Expect.stringEquals('xyz', value1.primitiveValue.slowToString());
-    Expect.stringEquals('xyz', value2.primitiveValue.slowToString());
+    Expect.stringEquals('xyz', value1.primitiveValue);
+    Expect.stringEquals('xyz', value2.primitiveValue);
 
     checkPosition(
         annotation1, annotation1.cachedNode, source4, compiler.reporter);
     checkPosition(
         annotation1, annotation2.cachedNode, source4, compiler.reporter);
   });
 }
 
 void testClassMetadata() {
   checkAnnotation('Foo', 'class Foo {}', isTopLevelOnly: true);
@@ skipping 28 matching lines @@
           LibraryElement element = compiler.libraryLoader.lookupLibrary(uri);
           Expect.isNotNull(element, 'Cannot find $uri');
 
           List<MetadataAnnotation> metadata = extractMetadata(element);
           Expect.equals(1, metadata.length);
 
           PartialMetadataAnnotation annotation = metadata.first;
           annotation.ensureResolved(compiler.resolution);
           PrimitiveConstantValue value =
               compiler.constants.getConstantValue(annotation.constant);
-          Expect.stringEquals('xyz', value.primitiveValue.slowToString());
+          Expect.stringEquals('xyz', value.primitiveValue);
 
           checkPosition(
               annotation, annotation.cachedNode, source, compiler.reporter);
         }));
   }
 
   var source;
 
   source = """@native
               library foo;
@@ skipping 26 matching lines @@
   compileAndCheckLibrary(
       source, (e) => e.compilationUnits.first.partTag.metadata);
 }
 
 void main() {
   testClassMetadata();
   testTopLevelMethodMetadata();
   testTopLevelFieldMetadata();
   testLibraryTags();
 }