Simplify runtime type support.

sdk/lib/_internal/compiler/implementation/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.
 
 part of ssa;
 
 class SsaCodeGeneratorTask extends CompilerTask {
 
   final JavaScriptBackend backend;
 
@@ skipping 2406 matching lines @@
       checkType(input, type);
       attachLocationToLast(node);
     }
     if (node.hasTypeInfo()) {
       InterfaceType interfaceType = type;
       ClassElement cls = type.element;
       Link<DartType> arguments = interfaceType.arguments;
       js.Expression result = pop();
       for (TypeVariableType typeVariable in cls.typeVariables) {
         use(node.typeInfoCall);
-        // TODO(johnniwinther): Retrieve the type name properly and not through
-        // [toString]. Note: Two cases below [typeVariable] and
-        // [arguments.head].
-        js.PropertyAccess field =
-            new js.PropertyAccess.field(pop(), typeVariable.toString());
+        int index = RuntimeTypeInformation.getTypeVariableIndex(typeVariable);
+        js.PropertyAccess field = new js.PropertyAccess.indexed(pop(), index);
         RuntimeTypeInformation rti = backend.rti;
-        String typeName = rti.buildStringRepresentation(arguments.head);
+        String typeName = rti.getStringRepresentation(arguments.head);
         js.Expression genericName = new js.LiteralString("'$typeName'");
         js.Binary eqTest = new js.Binary('===', field, genericName);
         // Also test for 'undefined' in case the object does not have
         // any type variable.
         js.Prefix undefinedTest = new js.Prefix('!', field);
         result = new js.Binary(
             '&&', result, new js.Binary('||', undefinedTest, eqTest));
+        arguments = arguments.tail;
       }
       push(result, node);
     }
     if (node.nullOk) {
       checkNull(input);
       push(new js.Binary('||', pop(), pop()), node);
     }
   }
 
   void visitTypeConversion(HTypeConversion node) {
@@ skipping 603 matching lines @@
   if (leftType.canBeNull() && rightType.canBeNull()) {
     if (left.isConstantNull() || right.isConstantNull() ||
         (leftType.isPrimitive() && leftType == rightType)) {
       return '==';
     }
     return null;
   } else {
     return '===';
   }
 }