Cleanup DOM after DoubleClickEventSinkTest tests complete

Review at http://gwt-code-reviews.appspot.com/1150801

Review by: jgw@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@9292 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/user/test/com/google/gwt/user/client/DoubleClickEventSinkTest.java b/user/test/com/google/gwt/user/client/DoubleClickEventSinkTest.java
index 200404a..b37ddcf 100644
--- a/user/test/com/google/gwt/user/client/DoubleClickEventSinkTest.java
+++ b/user/test/com/google/gwt/user/client/DoubleClickEventSinkTest.java
@@ -93,6 +93,13 @@
     verifyEventSinkOnAddHandler(new Label(), false);
   }
 
+  @Override
+  protected void gwtTearDown() throws Exception {
+    // clean up after ourselves
+    RootPanel.get().clear();
+    super.gwtTearDown();
+  }
+
   private boolean isDoubleClickEventSunk(Element e) {
     return (DOM.getEventsSunk(e) & Event.ONDBLCLICK) != 0;
   }