Use entities in code_emitter_task

pkg/compiler/lib/src/ssa/builder.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:collection';
 
 import 'package:js_runtime/shared/embedded_names.dart';
 
 import '../closure.dart';
 import '../common.dart';
@@ skipping 2941 matching lines @@
     if (node.arguments.isEmpty || !node.arguments.tail.isEmpty) {
       reporter.internalError(
           node.argumentsNode, '"$name" requires exactly one argument.');
     }
     ast.Node closure = node.arguments.head;
     Element element = elements[closure];
     if (!Elements.isStaticOrTopLevelFunction(element)) {
       reporter.internalError(
           closure, '"$name" requires a static or top-level method.');
     }
-    FunctionElement function = element;
+    MethodElement function = element;
     // TODO(johnniwinther): Try to eliminate the need to distinguish declaration
     // and implementation signatures. Currently it is need because the
     // signatures have different elements for parameters.
     FunctionElement implementation = function.implementation;
     FunctionSignature params = implementation.functionSignature;
     if (params.optionalParameterCount != 0) {
       reporter.internalError(
           closure, '"$name" does not handle closure with optional parameters.');
     }
 
@@ skipping 3799 matching lines @@
       this.oldReturnLocal,
       this.oldReturnType,
       this.oldResolvedAst,
       this.oldStack,
       this.oldLocalsHandler,
       this.inTryStatement,
       this.allFunctionsCalledOnce,
       this.oldElementInferenceResults)
       : super(function);
 }