Paper bag fix GlobalKey application group removal

Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/src/main/java/com/google/gwtexpui/globalkey/client/GlobalKey.java b/src/main/java/com/google/gwtexpui/globalkey/client/GlobalKey.java
index 9386bd9..08d4233 100644
--- a/src/main/java/com/google/gwtexpui/globalkey/client/GlobalKey.java
+++ b/src/main/java/com/google/gwtexpui/globalkey/client/GlobalKey.java
@@ -50,7 +50,7 @@
       @Override
       public void removeHandler() {
         keys.remove(key);
-        keyApplication.add(key);
+        keyApplication.remove(key);
       }
     };
   }