Fixed broken keyboard events in CustomButton.

Patch by: ecc
Review by: jgw



git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@2376 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/user/src/com/google/gwt/user/client/ui/CustomButton.java b/user/src/com/google/gwt/user/client/ui/CustomButton.java
index 87da861..d08c817 100644
--- a/user/src/com/google/gwt/user/client/ui/CustomButton.java
+++ b/user/src/com/google/gwt/user/client/ui/CustomButton.java
@@ -408,7 +408,7 @@
     // Use FocusPanel.impl rather than FocusWidget because only FocusPanel.impl
     // works across browsers to create a focusable element.
     super(FocusPanel.impl.createFocusable());
-    sinkEvents(Event.ONCLICK | Event.MOUSEEVENTS | Event.FOCUSEVENTS);
+    sinkEvents(Event.ONCLICK | Event.MOUSEEVENTS | Event.FOCUSEVENTS | Event.KEYEVENTS);
     setUpFace(createFace(null, "up", UP));
     setStyleName(STYLENAME_DEFAULT);