Avoid eager enqueueing from resolution

tests/compiler/dart2js/minimal_resolution_test.dart

 // Copyright (c) 2015, 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.
 
 // Test that elements are not needlessly required by dart2js.
 
 import 'package:async_helper/async_helper.dart';
 import 'package:compiler/src/compiler.dart';
+import 'package:compiler/src/elements/elements.dart';
+import 'package:compiler/src/enqueue.dart';
+import 'package:compiler/src/js_backend/js_backend.dart';
 import 'package:expect/expect.dart';
 import 'memory_compiler.dart';
 
 main() {
   asyncTest(() async {
     await analyze('main() {}');
     await analyze('main() => proxy;', proxyConstant: true);
+    await analyze('@deprecated main() {}');
+    await analyze('@deprecated main() => deprecated;', deprecatedClass: true);
+    await analyze('main() => deprecated;', deprecatedClass: true);
   });
 }
 
+void checkInstantiated(Compiler compiler, ClassElement cls, bool expected) {
+  ResolutionEnqueuer enqueuer = compiler.enqueuer.resolution;
+  bool isInstantiated =
+      enqueuer.universe.directlyInstantiatedClasses.contains(cls);
+  bool isProcessed = enqueuer.isClassProcessed(cls);
+  Expect.equals(expected, isInstantiated,
+      'Unexpected instantiation state of class $cls.');
+  Expect.equals(expected, isProcessed,
+      'Unexpected processing state of class $cls.');
+}
+
 analyze(String code,
-        {bool proxyConstant: false}) async {
+        {bool proxyConstant: false,
+         bool deprecatedClass: false}) async {
   CompilationResult result = await runCompiler(
       memorySourceFiles: {'main.dart': code},
       options: ['--analyze-only']);
   Expect.isTrue(result.isSuccess);
   Compiler compiler = result.compiler;
-  Expect.equals(proxyConstant, compiler.proxyConstant != null);
+  Expect.equals(proxyConstant, compiler.proxyConstant != null,
+      "Unexpected computation of proxy constant.");
+
+  checkInstantiated(
+      compiler, compiler.coreLibrary.find('_Proxy'), proxyConstant);
+  checkInstantiated(
+      compiler, compiler.coreLibrary.find('Deprecated'), deprecatedClass);
+
+  LibraryElement jsHelperLibrary =
+      compiler.libraryLoader.lookupLibrary(JavaScriptBackend.DART_JS_HELPER);
+  jsHelperLibrary.forEachLocalMember((Element element) {
+    Uri uri = element.compilationUnit.script.resourceUri;
+    if (element.isClass && uri.path.endsWith('annotations.dart')) {
+      checkInstantiated(compiler, element, false);
+    }
+  });
 }