remove workaround for MethodMirror.metadata

pkg/polymer/lib/src/declaration.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.
 
 part of polymer;
 
 /**
  * **Warning**: this class is experiental and subject to change.
  *
  * The implementation for the `polymer-element` element.
@@ skipping 472 matching lines @@
    * observe the associated properties.
    */
   void explodeObservers(ClassMirror cls) {
     if (cls == _htmlElementType) return;
 
     explodeObservers(cls.superclass);
     for (var method in cls.declarations.values) {
       if (method is! MethodMirror || method.isStatic
           || !method.isRegularMethod) continue;
 
-      for (var meta in _safeGetMetadata(method)) {
+      for (var meta in method.metadata) {
         if (meta.reflectee is! ObserveProperty) continue;
 
         if (_observe == null) _observe = new HashMap();
 
         for (String name in meta.reflectee.names) {
           _observe.putIfAbsent(new PropertyPath(name), () => [])
               .add(method.simpleName);
         }
       }
     }
@@ skipping 88 matching lines @@
     // bug introduced between Chrome 31 and 32. After 32
     // JsClassMirror.declarations on Object calls
     // JsClassMirror.typeVariables, which tries to get the _jsConstructor's
     // .prototype["<>"]. This ends up getting the "" property instead, maybe
     // because "<>" doesn't exist, and gets ";" which then blows up because
     // the code later on expects a List of ints.
   } while (cls != _objectType);
   return null;
 }
 
-List _safeGetMetadata(MethodMirror method) {
-  // TODO(jmesserly): dart2js blows up getting metadata from methods in some
-  // cases. Why does this happen? It seems like the culprit might be named
-  // arguments. Unfortunately even calling method.parameters also
-  // triggers the bug in computeFunctionRti. For now we guard against it
-  // with this check.
-  try {
-    return method.metadata;
-  } catch (e) {
-    return [];
-  }
-}
-
 bool _hasSetter(ClassMirror cls, MethodMirror getter) {
   var setterName = new Symbol('${MirrorSystem.getName(getter.simpleName)}=');
   var mirror = cls.declarations[setterName];
   return mirror is MethodMirror && mirror.isSetter;
 }
 
 
 /** Attribute prefix used for declarative event handlers. */
 const _EVENT_PREFIX = 'on-';
 
@@ skipping 94 matching lines @@
 
 // Dart note: we need this function because we have additional renames JS does
 // not have. The JS renames are simply case differences, whereas we have ones
 // like doubleclick -> dblclick and stripping the webkit prefix.
 String _eventNameFromType(String eventType) {
   final result = _reverseEventTranslations[eventType];
   return result != null ? result : eventType;
 }
 
 final _ATTRIBUTES_REGEX = new RegExp(r'\s|,');