Support user generated custom native JS classes.

pkg/compiler/lib/src/js_emitter/full_emitter/setup_program_builder.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.
 
 part of dart2js.js_emitter.full_emitter;
 
 // TODO(ahe): Share these with js_helper.dart.
 const FUNCTION_INDEX = 0;
 const NAME_INDEX = 1;
 const CALL_NAME_INDEX = 2;
@@ skipping 109 matching lines @@
      'classFieldsExtractor': classFieldsExtractorAccess,
      'instanceFromClassId': instanceFromClassIdAccess,
      'initializeEmptyInstance': initializeEmptyInstanceAccess,
      'allClasses': allClassesAccess,
      'debugFastObjects': DEBUG_FAST_OBJECTS,
      'isTreeShakingDisabled': backend.isTreeShakingDisabled,
      'precompiled': precompiledAccess,
      'finishedClassesAccess': finishedClassesAccess,
      'needsMixinSupport': emitter.needsMixinSupport,
      'needsNativeSupport': program.needsNativeSupport,
+     'enabledJsInterop': backend.jsInteropAnalysis.enabledJsInterop,
+     'jsInteropBoostrap':backend.jsInteropAnalysis.buildJsInteropBootstrap(),
      'isInterceptorClass': namer.operatorIs(backend.jsInterceptorClass),
      'isObject' : namer.operatorIs(compiler.objectClass),
      'specProperty': js.string(namer.nativeSpecProperty),
      'trivialNsmHandlers': emitter.buildTrivialNsmHandlers(),
      'hasRetainedMetadata': backend.hasRetainedMetadata,
      'types': typesAccess,
      'objectClassName': js.quoteName(
          namer.runtimeTypeName(compiler.objectClass)),
      'needsStructuredMemberInfo': emitter.needsStructuredMemberInfo,
      'usesMangledNames':
           compiler.mirrorsLibrary != null || compiler.enabledFunctionApply,
      'tearOffCode': buildTearOffCode(backend),
      'nativeInfoHandler': nativeInfoHandler,
      'operatorIsPrefix' : js.string(namer.operatorIsPrefix),
      'deferredActionString': js.string(namer.deferredAction)};
-
    String skeleton = '''
 function $setupProgramName(programData, typesOffset) {
   "use strict";
   if (#needsClassSupport) {
 
     function generateAccessor(fieldDescriptor, accessors, cls) {
       var fieldInformation = fieldDescriptor.split("-");
       var field = fieldInformation[0];
       var len = field.length;
       var code = field.charCodeAt(len - 1);
@@ skipping 591 matching lines @@
           mangledNames[name] = reflectionName;
           funcs[0].$reflectionNameField = reflectionName;
           funcs[0].$metadataIndexField = unmangledNameIndex + 1;
           // The following line installs the [${JsGetName.CALL_CATCH_ALL}]
           // property for closures.
           if (optionalParameterCount) prototype[unmangledName + "*"] = funcs[0];
         }
       }
     }
 
+    if (#enabledJsInterop) {
+      #jsInteropBoostrap
+    }
     #tearOffCode;
   }
 
   if (#hasIncrementalSupport) {
     #incrementalHelper.addStubs = addStubs;
   }
 
   var functionCounter = 0;
   if (!#libraries) #libraries = [];
   if (!#mangledNames) #mangledNames = map();
@@ skipping 81 matching lines @@
 (function() {
   var result = $array[$index];
   if ($check) {
     throw new Error(
         name + ": expected value of type \'$type\' at index " + ($index) +
         " but got " + (typeof result));
   }
   return result;
 })()''';
 }