Add support for metadata annotation syntax (issue 4056)

compiler/java/com/google/dart/compiler/type/TypeAnalyzer.java

 // 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.
 
 package com.google.dart.compiler.type;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Joiner;
 import com.google.common.base.Objects;
 import com.google.common.collect.ArrayListMultimap;
@@ skipping 2868 matching lines @@
       }
 
       @Override
       public Void visitMethodDefinition(DartMethodDefinition node) {
         MethodElement method = node.getElement();
         String name = method.getName();
         if (superMembers != null && !method.isConstructor()) {
           Collection<Element> overridden = superMembers.removeAll(name);
           Elements.setOverridden(method, ImmutableSet.copyOf(overridden));
           // Check for invalid @override metadata.
-          if (overridden.isEmpty() && node.getMetadata().isOverride()) {
+          if (overridden.isEmpty() && node.getObsoleteMetadata().isOverride()) {
             typeError(node.getName(), ResolverErrorCode.INVALID_OVERRIDE_METADATA);
           }
           // Check that override is valid.
           for (Element superElement : overridden) {
             if (!(method.isStatic() && superElement.getModifiers().isStatic())) {
               if (canOverride(node.getName(), method.getModifiers(), superElement)
                   && !superElement.getModifiers().isStatic()) {
                 switch (superElement.getKind()) {
                   case METHOD:
                     checkOverride(node.getName(), method, superElement);
@@ skipping 149 matching lines @@
         for (VariableElement v : parameters) {
           if (v.isNamed()) {
             named.add(v);
           }
         }
         return named;
       }
     }
   }
 }