Move IS_INDEXABLE_FIELD to JsGetName.

pkg/compiler/lib/src/js_backend/namer.dart

 // Copyright (c) 2011, 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;
 
 /**
  * Assigns JavaScript identifiers to Dart variables, class-names and members.
  *
  * Names are generated through three stages:
@@ skipping 430 matching lines @@
       case JsGetName.FUNCTION_TYPE_VOID_RETURN_TAG:
         return functionTypeVoidReturnTag;
       case JsGetName.FUNCTION_TYPE_RETURN_TYPE_TAG:
         return functionTypeReturnTypeTag;
       case JsGetName.FUNCTION_TYPE_REQUIRED_PARAMETERS_TAG:
         return functionTypeRequiredParametersTag;
       case JsGetName.FUNCTION_TYPE_OPTIONAL_PARAMETERS_TAG:
         return functionTypeOptionalParametersTag;
       case JsGetName.FUNCTION_TYPE_NAMED_PARAMETERS_TAG:
         return functionTypeNamedParametersTag;
+      case JsGetName.IS_INDEXABLE_FIELD_NAME:
+        Element cls = backend.findHelper('JavaScriptIndexingBehavior');
+        return operatorIs(cls);
       default:
         compiler.reportError(
           node, MessageKind.GENERIC,
           {'text': 'Error: Namer has no name for "$name".'});
         return 'BROKEN';
     }
   }
 
   /// Disambiguated name for [constant].
   ///
@@ skipping 1314 matching lines @@
         if (!first) {
           sb.write('_');
         }
         sb.write('_');
         visit(parameter);
         first = true;
       }
     }
   }
 }