Fix a pair of issues in the Dart code for the front end.

pkg/kernel/lib/binary/ast_to_binary.dart

 // Copyright (c) 2016, 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 kernel.ast_to_binary;
 
 import '../ast.dart';
 import '../import_table.dart';
 import 'tag.dart';
 import 'dart:convert';
 import 'dart:typed_data';
@@ skipping 1020 matching lines @@
       : predicate = predicate,
         super(sink);
 
   void writeProgramFile(Program program) {
     program.computeCanonicalNames();
     writeMagicWord(Tag.ProgramFile);
     _stringIndexer.scanProgram(program);
     writeStringTable(_stringIndexer);
     writeUriToSource(program);
     writeLinkTable(program);
-    writeList(program.libraries.where(predicate), writeNode);
+    writeList(program.libraries.where(predicate).toList(), writeNode);
     writeMemberReference(program.mainMethod, allowNull: true);
     _flush();
   }
 }
 
 class VariableIndexer {
   final Map<VariableDeclaration, int> index = <VariableDeclaration, int>{};
   final List<int> scopes = <int>[];
   int stackHeight = 0;
 
@@ skipping 281 matching lines @@
   void flush() {
     _sink.add(_buffer.sublist(0, length));
     _buffer = new Uint8List(SIZE);
     length = 0;
   }
 
   void flushAndDestroy() {
     _sink.add(_buffer.sublist(0, length));
   }
 }