Add interfaces for a new compiler API.

tests/compiler/dart2js/missing_file_test.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.
 
 // Test that the compiler can handle imports when package root has not been set.
 
 library dart2js.test.missing_file;
 
+import 'dart:async';
+import 'package:async_helper/async_helper.dart';
+import 'package:compiler/src/dart2jslib.dart';
 import 'package:expect/expect.dart';
-import "package:async_helper/async_helper.dart";
-import 'memory_source_file_helper.dart';
-
-import 'package:compiler/src/dart2jslib.dart'
-       show NullSink;
-
-import 'package:compiler/compiler.dart'
-       show DiagnosticHandler, Diagnostic;
-
-import 'dart:async';
+import 'memory_compiler.dart';
 
 const MEMORY_SOURCE_FILES = const {
   'main.dart': '''
 
 import 'foo.dart';
 
 main() {}
 ''',
 };
 
 Future runCompiler(Uri main, String expectedMessage) {
   print("\n\n\n");
-  Uri script = currentDirectory.resolveUri(Platform.script);
-  Uri libraryRoot = script.resolve('../../../sdk/');
-  Uri packageRoot = script.resolve('./packages/');
 
-  var provider = new MemorySourceFileProvider(MEMORY_SOURCE_FILES);
-  var handler = new FormattingDiagnosticHandler(provider);
-  var errors = [];
-
-  void diagnosticHandler(Uri uri, int begin, int end, String message,
-                         Diagnostic kind) {
-    if (kind == Diagnostic.ERROR) {
-      errors.add(message);
-    }
-    handler(uri, begin, end, message, kind);
-  }
-
-
-  EventSink<String> outputProvider(String name, String extension) {
-    if (name != '') throw 'Attempt to output file "$name.$extension"';
-    return new NullSink('$name.$extension');
-  }
-
-  Compiler compiler = new Compiler(provider,
-                                   outputProvider,
-                                   diagnosticHandler,
-                                   libraryRoot,
-                                   packageRoot,
-                                   [],
-                                   {});
+  DiagnosticCollector diagnostics = new DiagnosticCollector();
+  OutputCollector output = new OutputCollector();
+  Compiler compiler = compilerFor(
+      MEMORY_SOURCE_FILES,
+      diagnosticHandler: diagnostics,
+      outputProvider: output);
 
   return compiler.run(main).then((_) {
-    Expect.equals(1, errors.length);
-    Expect.equals(expectedMessage,
-                  errors[0]);
+    Expect.isFalse(output.hasExtraOutput);
+    Expect.equals(1, diagnostics.errors.length);
+    Expect.equals(expectedMessage, diagnostics.errors.first.message);
   });
 }
 
 void main() {
   asyncTest(() => Future.forEach([
   () => runCompiler(
       Uri.parse('memory:main.dart'),
       "Can't read 'memory:foo.dart' "
       "(Exception: No such file memory:foo.dart)."),
   () => runCompiler(
       Uri.parse('memory:foo.dart'),
       "Exception: No such file memory:foo.dart"),
   () => runCompiler(
       Uri.parse('dart:foo'),
       "Library not found 'dart:foo'."),
   ], (f) => f()));
 }