Remove frog from the repository.

frog/file_system_memory.dart

Index: frog/file_system_memory.dart
diff --git a/frog/file_system_memory.dart b/frog/file_system_memory.dart
deleted file mode 100644
index 4373f38900ef5b4b603f8b902f3c3305e376157a..0000000000000000000000000000000000000000
--- a/frog/file_system_memory.dart
+++ /dev/null
@@ -1,28 +0,0 @@
-// Copyright (c) 2011, 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('file_system_memory');
-
-#import('file_system.dart');
-
-/**
- * [FileSystem] implementation a memory buffer.
- */
-class MemoryFileSystem implements FileSystem {
-  StringBuffer buffer;
-
-  MemoryFileSystem() : this.buffer = new StringBuffer();
-
-  void writeString(String outfile, String text) {
-    buffer.add(text);
-  }
-
-  String readAll(String filename) {
-    return buffer.toString();
-  }
-
-  bool fileExists(String filename) {
-    return true;
-  }
-}