Use specific messages for const constructor with body.

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.
 
 part of ssa;
 
 class SsaFunctionCompiler implements FunctionCompiler {
   final SsaCodeGeneratorTask generator;
   final SsaBuilderTask builder;
   final SsaOptimizerTask optimizer;
@@ skipping 1736 matching lines @@
    * creates a new constructor body, if none can be found.
    *
    * Returns [:null:] if the constructor does not have a body.
    */
   ConstructorBodyElement getConstructorBody(FunctionElement constructor) {
     assert(constructor.isGenerativeConstructor);
     assert(invariant(constructor, constructor.isImplementation));
     if (constructor.isSynthesized) return null;
     ast.FunctionExpression node = constructor.node;
     // If we know the body doesn't have any code, we don't generate it.
-    if (!node.hasBody()) return null;
-    if (node.hasEmptyBody()) return null;
+    if (!node.hasBody) return null;
+    if (node.hasEmptyBody) return null;
     ClassElement classElement = constructor.enclosingClass;
     ConstructorBodyElement bodyElement;
     classElement.forEachBackendMember((Element backendMember) {
       if (backendMember.isGenerativeConstructorBody) {
         ConstructorBodyElement body = backendMember;
         if (body.constructor == constructor) {
           // TODO(kasperl): Find a way of stopping the iteration
           // through the backend members.
           bodyElement = backendMember;
         }
@@ skipping 7468 matching lines @@
     if (unaliased is TypedefType) throw 'unable to unalias $type';
     unaliased.accept(this, builder);
   }
 
   void visitDynamicType(DynamicType type, SsaBuilder builder) {
     JavaScriptBackend backend = builder.compiler.backend;
     ClassElement cls = backend.helpers.DynamicRuntimeType;
     builder.push(new HDynamicType(type, new TypeMask.exact(cls, classWorld)));
   }
 }