Prevents double-escaping of characters by keeping Window.createUrlBuilder() consistent with UrlBuilder.buildString().

Review at http://gwt-code-reviews.appspot.com/1528805

Review by: jlabanca@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@10570 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/user/src/com/google/gwt/user/client/Window.java b/user/src/com/google/gwt/user/client/Window.java
index 9c7339b..aec4a14 100644
--- a/user/src/com/google/gwt/user/client/Window.java
+++ b/user/src/com/google/gwt/user/client/Window.java
@@ -145,7 +145,8 @@
       }
       String hash = getHash();
       if (hash != null && hash.length() > 0) {
-        builder.setHash(hash);
+        // Decode the hash now, because UrlBuilder.buildString() later encodes it.
+        builder.setHash(URL.decodeQueryString(hash));
       }
       String port = getPort();
       if (port != null && port.length() > 0) {