Added a flag package-root for users to define where the package directory is.

pkg/docgen/lib/src/dart2js_mirrors.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.
-
-library dart2js_util;
-
-// TODO(tmandel): This is a temporary copy of the dart2js_mirrors.dart
-//   file in the dartdoc folder. One of the two should be deleted
-//   when docgen can replace dartdoc.
-
-import 'dart:async' show Future;
-import 'dart:io' show Path;
-
-import '../../../../sdk/lib/_internal/compiler/compiler.dart' as api;
-import '../../../../sdk/lib/_internal/compiler/implementation/mirrors/dart2js_mirror.dart' 
-    as dart2js show analyze, Dart2JsMirrorSystem;
-import '../../../../sdk/lib/_internal/compiler/implementation/mirrors/mirrors.dart'
-    show MirrorSystem;
-import '../../../../sdk/lib/_internal/compiler/implementation/source_file_provider.dart'
-    show FormattingDiagnosticHandler, SourceFileProvider;
-import '../../../../sdk/lib/_internal/compiler/implementation/filenames.dart'
-    show appendSlash, currentDirectory;
-
-// TODO(johnniwinther): Support client configurable providers.
-
-/**
- * Returns a future that completes to a non-null String when [script]
- * has been successfully compiled.
- */
-// TODO(amouravski): Remove this method and call dart2js via a process instead.
-Future<String> compile(Path script,
-                       Path libraryRoot,
-                       {Path packageRoot,
-                        List<String> options: const <String>[],
-                        api.DiagnosticHandler diagnosticHandler}) {
-  SourceFileProvider provider = new SourceFileProvider();
-  if (diagnosticHandler == null) {
-    diagnosticHandler =
-        new FormattingDiagnosticHandler(provider).diagnosticHandler;
-  }
-  Uri scriptUri = currentDirectory.resolve(script.toString());
-  Uri libraryUri = currentDirectory.resolve(appendSlash('$libraryRoot'));
-  Uri packageUri = null;
-  if (packageRoot != null) {
-    packageUri = currentDirectory.resolve(appendSlash('$packageRoot'));
-  }
-  return api.compile(scriptUri, libraryUri, packageUri,
-      provider.readStringFromUri, diagnosticHandler, options);
-}
-
-/**
- * Analyzes set of libraries and provides a mirror system which can be used for
- * static inspection of the source code.
- */
-Future<MirrorSystem> analyze(List<Path> libraries,
-                             Path libraryRoot,
-                             {Path packageRoot,
-                              List<String> options: const <String>[],
-                              api.DiagnosticHandler diagnosticHandler}) {
-  SourceFileProvider provider = new SourceFileProvider();
-  if (diagnosticHandler == null) {
-    diagnosticHandler =
-        new FormattingDiagnosticHandler(provider).diagnosticHandler;
-  }
-  Uri libraryUri = currentDirectory.resolve(appendSlash('$libraryRoot'));
-  Uri packageUri = null;
-  if (packageRoot != null) {
-    packageUri = currentDirectory.resolve(appendSlash('$packageRoot'));
-  }
-  List<Uri> librariesUri = <Uri>[];
-  for (Path library in libraries) {
-    librariesUri.add(currentDirectory.resolve(library.toString()));
-  }
-  return dart2js.analyze(librariesUri, libraryUri, packageUri,
-                         provider.readStringFromUri, diagnosticHandler,
-                         options);
-}