Reapply dart2js: Dot-separated field-and-super descriptor string in classes.

sdk/lib/_internal/compiler/implementation/js_backend/native_emitter.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.
 
 part of js_backend;
 
 class NativeEmitter {
 
   CodeEmitterTask emitter;
   CodeBuffer nativeBuffer;
@@ skipping 72 matching lines @@
         const SourceString('hashCodeForNativeObject'));
     return backend.namer.isolateAccess(element);
   }
 
   String get defineNativeClassName
       => '${backend.namer.CURRENT_ISOLATE}.\$defineNativeClass';
 
   String get defineNativeClassFunction {
     return """
 function(cls, desc) {
-  var fields = desc[''] || [];
   var generateGetterSetter = ${emitter.generateGetterSetterFunction};
-  for (var i = 0; i < fields.length; i++) {
-    generateGetterSetter(fields[i], desc);
+  var fields = desc[''];
+  var fields_array = fields ? fields.split(',') : [];
+  for (var i = 0; i < fields_array.length; i++) {
+    generateGetterSetter(fields_array[i], desc);
   }
   var hasOwnProperty = Object.prototype.hasOwnProperty;
   for (var method in desc) {
-    if (method !== '') {
+    if (method) {  """/* Short version of: if (method != '') */"""
       if (hasOwnProperty.call(desc, method)) {
         $dynamicName(method)[cls] = desc[method];
       }
     }
   }
 }""";
   }
 
   void generateNativeLiteral(ClassElement classElement) {
     String quotedNative = classElement.nativeTagInfo.slowToString();
@@ skipping 42 matching lines @@
       generateNativeLiteral(classElement);
       // The native literal kind needs to be dealt with specially when
       // generating code for it.
       return;
     }
 
     CodeBuffer fieldBuffer = new CodeBuffer();
     CodeBuffer getterSetterBuffer = new CodeBuffer();
     CodeBuffer methodBuffer = new CodeBuffer();
 
-    emitter.emitClassFields(classElement, fieldBuffer, false);
+    emitter.emitClassFields(classElement, fieldBuffer, false, isNative: true);
     emitter.emitClassGettersSetters(classElement, getterSetterBuffer, false);
     emitter.emitInstanceMembers(classElement, methodBuffer, false);
 
     if (methodBuffer.isEmpty
         && fieldBuffer.isEmpty
         && getterSetterBuffer.isEmpty) {
       return;
     }
 
     String nativeTag = toNativeTag(classElement);
@@ skipping 392 matching lines @@
         if (!first) targetBuffer.add(",\n");
         targetBuffer.add(" $name: $function");
         first = false;
       });
       targetBuffer.add("\n});\n\n");
     }
     targetBuffer.add(nativeBuffer);
     targetBuffer.add('\n');
   }
 }