Clean up imports.

dart/site/try/poi/poi.dart

 // Copyright (c) 2014, 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 trydart.poi;
 
 import 'dart:async' show
     Completer,
-    Future,
-    Stream;
+    Future;
 
 import 'dart:io' show
     File,
     HttpClient,
     HttpClientRequest,
     HttpClientResponse,
     Platform,
     stdout;
 
 import 'dart:io' as io;
 
 import 'dart:convert' show
-    LineSplitter,
     UTF8;
 
 import 'package:dart2js_incremental/dart2js_incremental.dart' show
     reuseCompiler;
 
 import 'package:compiler/implementation/source_file_provider.dart' show
-    FormattingDiagnosticHandler,
-    SourceFileProvider;
+    FormattingDiagnosticHandler;
 
 import 'package:compiler/compiler.dart' as api;
 
 import 'package:compiler/implementation/dart2jslib.dart' show
     Compiler,
     Enqueuer,
     QueueFilter,
     WorkItem;
 
 import 'package:compiler/implementation/elements/visitor.dart' show
@@ skipping 667 matching lines @@
     buffer.write('\n');
     indented.write('}');
   }
 }
 
 modelx.ScopeX localScope(modelx.LibraryElementX element) => element.localScope;
 
 modelx.ImportScope importScope(modelx.LibraryElementX element) {
   return element.importScope;
 }