Remove backends.

compiler/java/com/google/dart/compiler/backend/js/ast/JsLiteral.java

Index: compiler/java/com/google/dart/compiler/backend/js/ast/JsLiteral.java
diff --git a/compiler/java/com/google/dart/compiler/backend/js/ast/JsLiteral.java b/compiler/java/com/google/dart/compiler/backend/js/ast/JsLiteral.java
deleted file mode 100644
index c87ae0c8af1c6f00ae049c201e43e7ceae52dc68..0000000000000000000000000000000000000000
--- a/compiler/java/com/google/dart/compiler/backend/js/ast/JsLiteral.java
+++ /dev/null
@@ -1,14 +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.
-
-package com.google.dart.compiler.backend.js.ast;
-
-/**
- * A JavaScript string literal expression.
- */
-public abstract class JsLiteral extends JsExpression implements CanBooleanEval {
-
-  protected JsLiteral() {
-  }
-}