Remove frog dependencies from lib/compiler.

frog/frog.dart

Index: frog/frog.dart
diff --git a/frog/frog.dart b/frog/frog.dart
deleted file mode 100644
index b2d8ba06ff869a5c8794bbe91e3cec29b4a4027f..0000000000000000000000000000000000000000
--- a/frog/frog.dart
+++ /dev/null
@@ -1,12 +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.
-
-#import('lang.dart', prefix: 'lang');
-#import('leg/frog_leg.dart', prefix: 'leg');
-#import('minfrog.dart', prefix: 'minfrog');
-
-void main() {
-  lang.legCompile = leg.compile;
-  minfrog.main();
-}