Alternative fix for the js-interop crash.

pkg/compiler/lib/src/apiimpl.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.
 
 library leg_apiimpl;
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'package:package_config/packages.dart';
@@ skipping 65 matching lines @@
       : this.options = options,
         this.platformConfigUri = resolvePlatformConfig(libraryRoot, options),
         super(
             outputProvider: outputProvider,
             enableTypeAssertions: hasOption(options, Flags.enableCheckedMode),
             enableUserAssertions: hasOption(options, Flags.enableCheckedMode),
             trustTypeAnnotations:
                 hasOption(options, Flags.trustTypeAnnotations),
             trustPrimitives:
                 hasOption(options, Flags.trustPrimitives),
+            trustJSInteropTypeAnnotations:
+                hasOption(options, Flags.trustJSInteropTypeAnnotations),
             enableMinification: hasOption(options, Flags.minify),
             useFrequencyNamer:
                 !hasOption(options, Flags.noFrequencyBasedMinification),
             preserveUris: hasOption(options, Flags.preserveUris),
             enableNativeLiveTypeAnalysis:
                 !hasOption(options, Flags.disableNativeLiveTypeAnalysis),
             emitJavaScript: !(hasOption(options, '--output-type=dart') ||
                               hasOption(options, '--output-type=dart-multi')),
             dart2dartMultiFile: hasOption(options, '--output-type=dart-multi'),
             generateSourceMap: !hasOption(options, Flags.noSourceMaps),
@@ skipping 465 matching lines @@
   Uri lookupLibraryUri(String libraryName) {
     assert(invariant(NO_LOCATION_SPANNABLE,
         sdkLibraries != null, message: "setupSdk() has not been run"));
     return sdkLibraries[libraryName];
   }
 
   Uri resolvePatchUri(String libraryName) {
     return backend.resolvePatchUri(libraryName, platformConfigUri);
   }
 }