Revert "Parse new library syntax."

dart/lib/compiler/implementation/tree/nodes.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.
 
 abstract class Visitor<R> {
   R visitBlock(Block node);
   R visitBreakStatement(BreakStatement node);
   R visitCascade(Cascade node);
   R visitCascadeReceiver(CascadeReceiver node);
   R visitCaseMatch(CaseMatch node);
@@ skipping 1575 matching lines @@
   visitChildren(Visitor visitor) {
     tag.accept(visitor);
     argument.accept(visitor);
     if (prefixIdentifier !== null) prefixIdentifier.accept(visitor);
     if (prefix !== null) prefix.accept(visitor);
   }
 
   Token getBeginToken() => beginToken;
 
   Token getEndToken() => endToken;
-
-  LibraryTag toLibraryTag() {
-    if (isImport()) {
-      Identifier prefixNode;
-      if (prefix !== null) {
-        SourceString source = prefix.dartString.source;
-        Token token = new StringToken.fromSource(IDENTIFIER_INFO, source,
-                                                 prefix.token.charOffset);
-        token.next = prefix.token.next;
-        prefixNode = new Identifier(token);
-      }
-      return new Import(tag.token, argument, prefixNode, null);
-    } else if (isLibrary()) {
-      return new LibraryName(tag.token, argument);
-    } else if (isSource()) {
-      return new Part(tag.token, argument);
-    } else {
-      throw 'Unknown script tag ${tag.token.slowToString()}';
-    }
-  }
-}
-
-class LibraryTag extends Node {
-  bool get isLibraryName => false;
-  bool get isImport => false;
-  bool get isExport => false;
-  bool get isPart => false;
-}
-
-class LibraryName extends LibraryTag {
-  final Expression name;
-
-  final Token libraryKeyword;
-
-  LibraryName(this.libraryKeyword, this.name);
-
-  bool get isLibraryName => true;
-
-  LibraryName asLibraryName() => this;
-
-  accept(Visitor visitor) => visitor.visitLibraryName(this);
-
-  visitChildren(Visitor visitor) => name.accept(visitor);
-
-  Token getBeginToken() => libraryKeyword;
-
-  Token getEndToken() => name.getEndToken().next;
-}
-
-class Import extends LibraryTag {
-  final LiteralString uri;
-  final Identifier prefix;
-  final NodeList combinators;
-
-  final Token importKeyword;
-
-  Import(this.importKeyword, this.uri, this.prefix, this.combinators);
-
-  bool get isImport => true;
-
-  Import asImport() => this;
-
-  accept(Visitor visitor) => visitor.visitImport(this);
-
-  visitChildren(Visitor visitor) {
-    uri.accept(visitor);
-    if (prefix !== null) prefix.accept(visitor);
-    if (combinators !== null) combinators.accept(visitor);
-  }
-
-  Token getBeginToken() => importKeyword;
-
-  Token getEndToken() {
-    if (combinators !== null) return combinators.getEndToken().next;
-    if (prefix !== null) return prefix.getEndToken().next;
-    return uri.getEndToken().next;
-  }
-}
-
-class Export extends LibraryTag {
-  final LiteralString uri;
-  final NodeList combinators;
-
-  final Token exportKeyword;
-
-  Export(this.exportKeyword, this.uri, this.combinators);
-
-  bool get isExport => true;
-
-  Export asExport() => this;
-
-  accept(Visitor visitor) => visitor.visitExport(this);
-
-  visitChildren(Visitor visitor) {
-    uri.accept(visitor);
-    if (combinators !== null) combinators.accept(visitor);
-  }
-
-  Token getBeginToken() => exportKeyword;
-
-  Token getEndToken() {
-    if (combinators !== null) return combinators.getEndToken().next;
-    return uri.getEndToken().next;
-  }
-}
-
-class Part extends LibraryTag {
-  final LiteralString uri;
-
-  final Token partKeyword;
-
-  Part(this.partKeyword, this.uri);
-
-  bool get isPart => true;
-
-  Part asPart() => this;
-
-  accept(Visitor visitor) => visitor.visitPart(this);
-
-  visitChildren(Visitor visitor) => uri.accept(visitor);
-
-  Token getBeginToken() => partKeyword;
-
-  Token getEndToken() => uri.getEndToken().next;
 }
 
 class Typedef extends Node {
   final TypeAnnotation returnType;
   final Identifier name;
   final NodeList typeParameters;
   final NodeList formals;
 
   final Token typedefKeyword;
   final Token endToken;
@@ skipping 163 matching lines @@
  * argument).
  *
  * TODO(ahe): This method is controversial, the team needs to discuss
  * if top-level methods are acceptable and what naming conventions to
  * use.
  */
 initializerDo(Node node, f(Node node)) {
   SendSet send = node.asSendSet();
   if (send !== null) return f(send.arguments.head);
 }