fixes #183, remove our InMemory* in favor of analyzer's impl

lib/src/in_memory.dart

-// Copyright (c) 2015, 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 dev_compiler.src.in_memory;
-
-import 'package:analyzer/src/generated/ast.dart';
-import 'package:analyzer/src/generated/engine.dart' show TimestampedData;
-import 'package:analyzer/src/generated/source.dart';
-import 'package:path/path.dart' as path;
-import 'package:source_span/source_span.dart';
-
-import 'dependency_graph.dart' show runtimeFilesForServerMode;
-
-/// Uri resolver that can load test files from memory.
-class InMemoryUriResolver extends UriResolver {
-  final Map<Uri, InMemorySource> files = <Uri, InMemorySource>{};
-
-  /// Whether to represent a non-existing file with a [TestSource] (default
-  /// behavior from analyzer), or to use null (possible when overriding the
-  /// package-url-resolvers.)
-  final bool representNonExistingFiles;
-
-  InMemoryUriResolver(Map<String, String> allFiles,
-      {this.representNonExistingFiles: true}) {
-    allFiles.forEach((key, value) {
-      var uri = key.startsWith('package:') ? Uri.parse(key) : new Uri.file(key);
-      files[uri] = new InMemorySource(uri, value);
-    });
-
-    // TODO(vsm): Separate flag here?
-    if (representNonExistingFiles) {
-      runtimeFilesForServerMode.forEach((filepath) {
-        var uri = Uri.parse('/dev_compiler_runtime/$filepath');
-        files[uri] =
-            new InMemorySource(uri, '/* test contents of $filepath */');
-      });
-    }
-  }
-
-  Source resolveAbsolute(Uri uri) {
-    if (uri.scheme != 'file' && uri.scheme != 'package') return null;
-    if (!representNonExistingFiles) return files[uri];
-    return files.putIfAbsent(uri, () => new InMemorySource(uri, null));
-  }
-}
-
-class InMemoryContents implements TimestampedData<String> {
-  int modificationTime;
-  String data;
-
-  InMemoryContents(this.modificationTime, this.data);
-}
-
-/// An in memory source file.
-class InMemorySource implements Source {
-  final Uri uri;
-  InMemoryContents contents;
-  final SourceFile _file;
-  final UriKind uriKind;
-
-  InMemorySource(uri, contents)
-      : uri = uri,
-        contents = new InMemoryContents(1, contents),
-        _file = contents != null ? new SourceFile(contents, url: uri) : null,
-        uriKind = uri.scheme == 'file' ? UriKind.FILE_URI : UriKind.PACKAGE_URI;
-
-  bool exists() => contents.data != null;
-
-  Source get source => this;
-
-  String _encoding;
-  String get encoding => _encoding != null ? _encoding : (_encoding = '$uri');
-
-  String get fullName => uri.path;
-
-  int get modificationStamp => contents.modificationTime;
-  String get shortName => path.basename(uri.path);
-
-  operator ==(other) => other is InMemorySource && uri == other.uri;
-  int get hashCode => uri.hashCode;
-  bool get isInSystemLibrary => false;
-
-  Uri resolveRelativeUri(Uri relativeUri) => uri.resolveUri(relativeUri);
-
-  SourceSpan spanFor(AstNode node) {
-    final begin = node is AnnotatedNode
-        ? node.firstTokenAfterCommentAndMetadata.offset
-        : node.offset;
-    return _file.span(begin, node.end);
-  }
-
-  String toString() => '[$runtimeType: $uri]';
-}