Dart: Simplifies the handle watcher. Various cleanups and bugfixes.

mojo/dart/embedder/test/dart_to_cpp_tests.dart

 // Copyright 2014 The Chromium Authors. 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:async';
 import 'dart:mojo_bindings' as bindings;
 import 'dart:mojo_core' as core;
 import 'dart:typed_data';
 
 import 'package:mojo/dart/embedder/test/dart_to_cpp.mojom.dart';
@@ skipping 21 matching lines @@
 
   EchoArgsList createEchoArgsList(List<EchoArgs> list) {
     return list.fold(null, (result, arg) {
       var element = new EchoArgsList();
       element.item = arg;
       element.next = result;
       return element;
     });
   }
 
-  void ping(params) {
+  void ping() {
     callPingResponse();
     _completer.complete(null);
   }
 
-  void echo(params) {
-    int numIterations = params.numIterations;
-    EchoArgs arg = params.arg;
+  void echo(int numIterations, EchoArgs arg) {
     if (arg.si64 > 0) {
       arg.si64 = BAD_VALUE;
     }
     if (arg.si32 > 0) {
       arg.si32 = BAD_VALUE;
     }
     if (arg.si16 > 0) {
       arg.si16 = BAD_VALUE;
     }
     if (arg.si8 > 0) {
@@ skipping 43 matching lines @@
   int mojoHandle = args[0];
   var rawHandle = new core.RawMojoHandle(mojoHandle);
   var endpoint = new core.MojoMessagePipeEndpoint(rawHandle);
   var dartSide = new DartSide(endpoint);
   dartSide.listen();
   dartSide.callStartTest();
   dartSide.future.then((_) {
     print('Success');
   });
 }