Redo "Dummy receiver optimization"

sdk/lib/_internal/compiler/implementation/js_backend/constant_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 ConstantEmitter  {
   ConstantReferenceEmitter _referenceEmitter;
   ConstantInitializerEmitter _initializerEmitter;
 
@@ skipping 126 matching lines @@
     return emitCanonicalVersion(constant);
   }
 
   jsAst.Expression visitConstructed(ConstructedConstant constant) {
     return emitCanonicalVersion(constant);
   }
 
   jsAst.Expression visitInterceptor(InterceptorConstant constant) {
     return emitCanonicalVersion(constant);
   }
+
+  jsAst.Expression visitDummyReceiver(DummyReceiverConstant constant) {
+    return new jsAst.LiteralNumber('0');
+  }
 }
 
 /**
  * Visitor for generating JavaScript expressions to initialize [Constant]s.
  * Do not use directly; use methods from [ConstantEmitter].
  */
 class ConstantInitializerEmitter implements ConstantVisitor<jsAst.Expression> {
   final Compiler compiler;
   final Namer namer;
   final ConstantReferenceEmitter referenceEmitter;
@@ skipping 149 matching lines @@
                           [typeName]);
   }
 
   jsAst.Expression visitInterceptor(InterceptorConstant constant) {
     return new jsAst.PropertyAccess.field(
         new jsAst.VariableUse(
             getJsConstructor(constant.dispatchedType.element)),
         'prototype');
   }
 
+  jsAst.Expression visitDummyReceiver(DummyReceiverConstant constant) {
+    return _reference(constant);
+  }
+
   jsAst.Expression visitConstructed(ConstructedConstant constant) {
     Element element = constant.type.element;
     if (element.isForeign(compiler)
         && element.name == 'JS_CONST') {
       StringConstant str = constant.fields[0];
       String value = str.value.slowToString();
       return new jsAst.LiteralExpression(stripComments(value));
     }
     jsAst.New instantiation = new jsAst.New(
         new jsAst.VariableUse(getJsConstructor(constant.type.element)),
@@ skipping 25 matching lines @@
           .map((DartType type) =>
               rti.getTypeRepresentationWithHashes(type, (_){}));
       jsAst.Expression argumentList =
           new jsAst.LiteralString('[${arguments.join(', ')}]');
       return new jsAst.Call(getHelperProperty(backend.getSetRuntimeTypeInfo()),
                             [value, argumentList]);
     }
     return value;
   }
 }