Fixed problems occuring when changing user in gerrit configuration

Bug: 399238
Change-Id: I255634bc9b3681f292190051daed22a4771d6e57
Signed-off-by: Tobias Pfeifer <to.pfeifer@sap.com>

org.eclipse.jgit/src/org/eclipse/jgit/transport/URIish.java

@@ -614,7 +614,7 @@ public class URIish implements Serializable {
 		}
 
 		if (getHost() != null) {
-			if (getUser() != null)
+			if (getUser() != null && getUser().length() > 0)
 				r.append('@');
 			r.append(escape(getHost(), false, escapeNonAscii));
 			if (getScheme() != null && getPort() > 0) {