Don't use magic strings/properties to communicate between compiler and runtime.

pkg/compiler/lib/src/ssa/codegen.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.
 
 import 'dart:math' as math;
 import '../common.dart';
 import '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/tasks.dart' show CompilerTask;
 import '../compiler.dart' show Compiler;
 import '../constants/constant_system.dart';
@@ skipping 2951 matching lines @@
         new js.ObjectInitializer(namedParameters)
       ];
       push(js.js(
           '#(#)', [accessHelper(helpers.buildNamedFunctionType), arguments]));
     }
   }
 
   void visitTypeInfoReadRaw(HTypeInfoReadRaw node) {
     use(node.inputs[0]);
     js.Expression receiver = pop();
-    push(js.js(r'#.#', [receiver, backend.namer.rtiFieldName]));
+    push(js.js(r'#.#', [receiver, backend.namer.rtiFieldJsName]));
   }
 
   void visitTypeInfoReadVariable(HTypeInfoReadVariable node) {
     TypeVariableEntity element = node.variable.element;
 
     int index = element.index;
     HInstruction object = node.object;
     use(object);
     js.Expression receiver = pop();
 
@@ skipping 71 matching lines @@
     registry.registerStaticUse(
         new StaticUse.staticInvoke(helperElement, CallStructure.ONE_ARG));
 
     use(node.inputs[0]);
     if (node.hasReceiver) {
       if (backend.interceptorData.isInterceptorClass(element.typeDeclaration)) {
         int index = element.index;
         js.Expression receiver = pop();
         js.Expression helper =
             backend.emitter.staticFunctionAccess(helperElement);
-        js.Expression rtiFieldName = backend.namer.rtiFieldName;
+        js.Expression rtiFieldName = backend.namer.rtiFieldJsName;
         push(js.js(r'#(#.# && #.#[#])', [
           helper,
           receiver,
           rtiFieldName,
           receiver,
           rtiFieldName,
           js.js.number(index)
         ]));
       } else {
         backend.emitter.registerReadTypeVariable(element);
@@ skipping 41 matching lines @@
     registry.registerStaticUse(new StaticUse.staticInvoke(
         helper, new CallStructure.unnamed(argumentCount)));
     return backend.emitter.staticFunctionAccess(helper);
   }
 
   @override
   void visitRef(HRef node) {
     visit(node.value);
   }
 }