Add FunctionElement.hasFunctionSignature.

dart/sdk/lib/_internal/compiler/implementation/elements/modelx.dart

 // Copyright (c) 2013, 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.
 
 library elements.modelx;
 
 import 'elements.dart';
 import '../constants/expressions.dart';
 import '../helpers/helpers.dart';  // Included for debug helpers.
 import '../tree/tree.dart';
@@ skipping 288 matching lines @@
   get origin => this;
   get immediateRedirectionTarget => unsupported();
   get nestedClosures => unsupported();
   get memberContext => unsupported();
   get executableContext => unsupported();
 
   bool get isRedirectingFactory => unsupported();
 
   computeSignature(compiler) => unsupported();
 
+  bool get hasFunctionSignature => false;
+
   get effectiveTarget => this;
 
   computeEffectiveTargetType(InterfaceType newType) => unsupported();
 
   get definingConstructor => null;
 
   FunctionElement asFunctionElement() => this;
 
   String get message => '${messageKind.message(messageArguments)}';
 
@@ skipping 1235 matching lines @@
         _hasNoBody = hasNoBody {
     assert(modifiers != null);
   }
 
   bool get isInstanceMember {
     return isClassMember
            && !isConstructor
            && !isStatic;
   }
 
+  bool get hasFunctionSignature => functionSignatureCache != null;
+
   FunctionSignature computeSignature(Compiler compiler) {
     if (functionSignatureCache != null) return functionSignatureCache;
     compiler.withCurrentElement(this, () {
       functionSignatureCache = compiler.resolver.resolveSignature(this);
     });
     return functionSignatureCache;
   }
 
   FunctionSignature get functionSignature {
     assert(invariant(this, functionSignatureCache != null,
@@ skipping 1134 matching lines @@
   AstElement get definingElement;
 
   bool get hasResolvedAst => definingElement.hasTreeElements;
 
   ResolvedAst get resolvedAst {
     return new ResolvedAst(declaration,
         definingElement.node, definingElement.treeElements);
   }
 
 }