Handle missing imports/exports/parts.

tests/compiler/dart2js/message_kind_test.dart

 // Copyright (c) 2013, 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 '../../../sdk/lib/_internal/compiler/implementation/dart2jslib.dart' show
     DualKind,
     MessageKind;
 
 import 'message_kind_helper.dart';
 
 import 'dart:mirrors';
 
 main() {
   ClassMirror cls = reflectClass(MessageKind);
   Map<String, MessageKind> kinds = <String, MessageKind>{};
   cls.variables.forEach((Symbol name, VariableMirror variable) {
     if (variable.isStatic) {
       var value = cls.getField(name).reflectee;
       if (value is MessageKind) {
         kinds[MirrorSystem.getName(name)] = value;
       } else if (value is DualKind) {
         kinds['${MirrorSystem.getName(name)}.error'] = value.error;
         kinds['${MirrorSystem.getName(name)}.warning'] = value.warning;
       } else {
         Expect.fail("Weird static field: '${MirrorSystem.getName(name)}'.");
       }
     }
   });
   List<String> names = kinds.keys.toList()..sort();
-  List<String> examples = <String>[];
+  Map<String, bool> examples = <String, bool>{};
   for (String name in names) {
     MessageKind kind = kinds[name];
+    bool expectNoHowToFix = false;
+    if (name == 'READ_SCRIPT_ERROR') {
+      // For this we can give no how-to-fix since the underlying error is
+      // unknown.
+      expectNoHowToFix = true;
+    }
     if (name == 'GENERIC' // Shouldn't be used.
         // We can't provoke a crash.
         || name == 'COMPILER_CRASHED'
         || name == 'PLEASE_REPORT_THE_CRASH'
         // We cannot provide examples for patch errors.
         || name.startsWith('PATCH_')) continue;
     if (kind.examples != null) {
-      examples.add(name);
+      examples[name] = expectNoHowToFix;
     } else {
       print("No example in '$name'");
     }
   };
   var cachedCompiler;
-  for (String name in examples) {
+  examples.forEach((String name, bool expectNoHowToFix) {
     Stopwatch sw = new Stopwatch()..start();
-    cachedCompiler = check(kinds[name], cachedCompiler);
+    cachedCompiler = check(kinds[name], cachedCompiler,
+                           expectNoHowToFix: expectNoHowToFix);
     sw.stop();
     print("Checked '$name' in ${sw.elapsedMilliseconds}ms.");
-  }
+  });
 }