Re-order, don't even enter the try block if there is nothing to do

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@668625 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/taskdefs/Definer.java

@@ -340,15 +340,15 @@ public abstract class Definer extends DefBase {
         if (message == null && !(file.isFile())) {
             message = "File " + file + " is not a file";
         }
-        try {
             if (message == null) {
+        try {
                 return FileUtils.getFileUtils().getFileURL(file);
-            }
         } catch (Exception ex) {
             message =
                 "File " + file + " cannot use as URL: "
                 + ex.toString();
         }
+            }
         // Here if there is an error
         switch (onError) {
             case OnError.FAIL_ALL: