Refactor Parsing to remove compiler dependency

tests/compiler/dart2js/compiler_test.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.
 
 import "dart:async";
+
+import "package:async_helper/async_helper.dart";
+import 'package:compiler/compiler.dart';
+import "package:compiler/src/elements/elements.dart";
 import "package:expect/expect.dart";
-import "package:async_helper/async_helper.dart";
-import "package:compiler/src/elements/elements.dart";
-import "package:compiler/src/resolution/members.dart";
-import "package:compiler/src/diagnostics/diagnostic_listener.dart";
+
 import "mock_compiler.dart";
-import "diagnostic_reporter_helper.dart";
-
-
-class CallbackMockCompiler extends MockCompiler {
-  CallbackReporter reporter;
-
-  CallbackMockCompiler() : super.internal() {
-    reporter = new CallbackReporter(super.reporter);
-  }
-
-}
-
-class CallbackReporter extends DiagnosticReporterWrapper {
-  final DiagnosticReporter reporter;
-
-  CallbackReporter(this.reporter);
-
-  var onError;
-  var onWarning;
-
-  setOnError(var f) => onError = f;
-  setOnWarning(var f) => onWarning = f;
-
-  void reportWarning(
-      DiagnosticMessage message,
-      [List<DiagnosticMessage> infos = const <DiagnosticMessage>[]]) {
-    if (onWarning != null) {
-      onWarning(this, message.spannable, message.message);
-    }
-    super.reportWarning(message, infos);
-  }
-
-  void reportError(
-      DiagnosticMessage message,
-      [List<DiagnosticMessage> infos = const <DiagnosticMessage>[]]) {
-    if (onError != null) {
-      onError(this, message.spannable, message.message);
-    }
-    super.reportError(message, infos);
-  }
-}
 
 Future testErrorHandling() {
   // Test that compiler.currentElement is set correctly when
   // reporting errors/warnings.
-  CallbackMockCompiler compiler = new CallbackMockCompiler();
+  MockCompiler compiler = new MockCompiler.internal();
   return compiler.init().then((_) {
-    ResolverVisitor visitor = compiler.resolverVisitor();
     compiler.parseScript('NoSuchPrefix.NoSuchType foo() {}');
     FunctionElement foo = compiler.mainApp.find('foo');
-    compiler.reporter.setOnWarning(
-        (c, n, m) => Expect.equals(foo, compiler.currentElement));
+    compiler.diagnosticHandler =
+        (Uri uri, int begin, int end, String message, Diagnostic kind) {
+      if (kind == Diagnostic.WARNING) {
+        Expect.equals(foo, compiler.currentElement);
+      }
+    };
     foo.computeType(compiler.resolution);
     Expect.equals(1, compiler.diagnosticCollector.warnings.length);
   });
 }
 
 main() {
   asyncTest(() => testErrorHandling());
 }