Remove backends.

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

Index: compiler/java/com/google/dart/compiler/backend/js/ast/JsRegExp.java
diff --git a/compiler/java/com/google/dart/compiler/backend/js/ast/JsRegExp.java b/compiler/java/com/google/dart/compiler/backend/js/ast/JsRegExp.java
deleted file mode 100644
index 158c7a5e0928a745a674407f51f2e80d7cd34350..0000000000000000000000000000000000000000
--- a/compiler/java/com/google/dart/compiler/backend/js/ast/JsRegExp.java
+++ /dev/null
@@ -1,64 +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 regular expression.
- */
-public final class JsRegExp extends JsValueLiteral {
-
-  private String flags;
-  private String pattern;
-
-  public JsRegExp() {
-  }
-
-  public String getFlags() {
-    return flags;
-  }
-
-  public String getPattern() {
-    return pattern;
-  }
-
-  @Override
-  public boolean isBooleanFalse() {
-    return false;
-  }
-
-  @Override
-  public boolean isBooleanTrue() {
-    return true;
-  }
-
-  @Override
-  public boolean isDefinitelyNotNull() {
-    return true;
-  }
-
-  @Override
-  public boolean isDefinitelyNull() {
-    return false;
-  }
-
-  public void setFlags(String suffix) {
-    this.flags = suffix;
-  }
-
-  public void setPattern(String re) {
-    this.pattern = re;
-  }
-
-  @Override
-  public void traverse(JsVisitor v, JsContext ctx) {
-    v.visit(this, ctx);
-    v.endVisit(this, ctx);
-  }
-
-  @Override
-  public NodeKind getKind() {
-    return NodeKind.REGEXP;
-  }
-}