Repeats and fixes the changes landed & reverted as CL 1789553003.

tests/compiler/dart2js/mock_compiler.dart

-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2016, 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.
 
 library mock_compiler;
 
-import "package:expect/expect.dart";
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:compiler/compiler.dart' as api;
-import 'package:compiler/compiler_new.dart' as new_api;
 import 'package:compiler/src/common/names.dart' show
     Uris;
 import 'package:compiler/src/constants/expressions.dart';
 import 'package:compiler/src/diagnostics/diagnostic_listener.dart';
 import 'package:compiler/src/diagnostics/source_span.dart';
 import 'package:compiler/src/diagnostics/spannable.dart';
 import 'package:compiler/src/elements/elements.dart';
-import 'package:compiler/src/js_backend/backend_helpers.dart'
-    show BackendHelpers;
-import 'package:compiler/src/js_backend/lookup_map_analysis.dart'
-    show LookupMapAnalysis;
+import 'package:compiler/src/js_backend/backend_helpers.dart' show
+    BackendHelpers;
+import 'package:compiler/src/js_backend/lookup_map_analysis.dart' show
+    LookupMapAnalysis;
 import 'package:compiler/src/io/source_file.dart';
+import 'package:compiler/src/options.dart' show
+    CompilerOptions;
 import 'package:compiler/src/resolution/members.dart';
 import 'package:compiler/src/resolution/registry.dart';
 import 'package:compiler/src/resolution/scope.dart';
 import 'package:compiler/src/resolution/tree_elements.dart';
 import 'package:compiler/src/script.dart';
 import 'package:compiler/src/tree/tree.dart';
 import 'package:compiler/src/old_to_new_api.dart';
 import 'parser_helper.dart';
 
-import 'package:compiler/src/elements/modelx.dart'
-    show ElementX,
-         LibraryElementX,
-         ErroneousElementX,
-         FunctionElementX;
+import 'package:compiler/src/elements/modelx.dart' show
+    ElementX,
+    LibraryElementX,
+    ErroneousElementX,
+    FunctionElementX;
 
 import 'package:compiler/src/compiler.dart';
 
-import 'package:compiler/src/deferred_load.dart'
-    show DeferredLoadTask,
-         OutputUnit;
+import 'package:compiler/src/deferred_load.dart' show
+    DeferredLoadTask,
+    OutputUnit;
 
 import 'mock_libraries.dart';
 import 'diagnostic_helper.dart';
 
 export 'diagnostic_helper.dart';
 
 final Uri PATCH_CORE = new Uri(scheme: 'patch', path: 'core');
 
 typedef String LibrarySourceProvider(Uri uri);
 
@@ skipping 26 matching lines @@
        bool trustTypeAnnotations: false,
        bool trustJSInteropTypeAnnotations: false,
        bool enableAsyncAwait: false,
        int this.expectedWarnings,
        int this.expectedErrors,
        api.CompilerOutputProvider outputProvider,
        String patchVersion,
        LibrarySourceProvider this.librariesOverride})
       : sourceFiles = new Map<String, SourceFile>(),
         testedPatchVersion = patchVersion,
-        super(options: new new_api.CompilerOptions(
+        super(options: new CompilerOptions(
               entryPoint: new Uri(scheme: 'mock'),
               libraryRoot: Uri.parse('placeholder_library_root_for_mock/'),
               enableTypeAssertions: enableTypeAssertions,
               enableUserAssertions: enableUserAssertions,
               disableInlining: disableInlining,
               enableAssertMessage: true,
               enableMinification: enableMinification,
               disableTypeInference: disableTypeInference,
               analyzeAll: analyzeAll,
               analyzeOnly: analyzeOnly,
               emitJavaScript: emitJavaScript,
               preserveComments: preserveComments,
               trustTypeAnnotations: trustTypeAnnotations,
               trustJSInteropTypeAnnotations: trustJSInteropTypeAnnotations,
-              diagnosticOptions:
-                  new DiagnosticOptions(shownPackageWarnings: const [])),
+              shownPackageWarnings: const []),
               outputProvider: new LegacyCompilerOutput(outputProvider)) {
 
     deferredLoadTask = new MockDeferredLoadTask(this);
 
     registerSource(Uris.dart_core,
                    buildLibrarySource(DEFAULT_CORE_LIBRARY, coreSource));
     registerSource(PATCH_CORE, DEFAULT_PATCH_CORE_SOURCE);
 
     registerSource(BackendHelpers.DART_JS_HELPER,
                    buildLibrarySource(DEFAULT_JS_HELPER_LIBRARY));
@@ skipping 253 matching lines @@
       trustTypeAnnotations: trustTypeAnnotations,
       enableTypeAssertions: enableTypeAssertions,
       enableUserAssertions: enableUserAssertions,
       expectedErrors: expectedErrors,
       expectedWarnings: expectedWarnings,
       outputProvider: outputProvider);
   compiler.registerSource(uri, code);
   compiler.diagnosticHandler = createHandler(compiler, code);
   return compiler;
 }