Fixed a bug computing module creation time.  Min vs. Max, doh.

Review by: bobv


git-svn-id: https://google-web-toolkit.googlecode.com/svn/releases/1.6@4316 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/dev/core/src/com/google/gwt/dev/cfg/ModuleDef.java b/dev/core/src/com/google/gwt/dev/cfg/ModuleDef.java
index 7c9fb94..6ab4a8f 100644
--- a/dev/core/src/com/google/gwt/dev/cfg/ModuleDef.java
+++ b/dev/core/src/com/google/gwt/dev/cfg/ModuleDef.java
@@ -42,7 +42,6 @@
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
@@ -355,14 +354,13 @@
   }
 
   public long lastModified() {
-    long lastModified = moduleDefCreationTime;
-    for (Iterator<File> iter = gwtXmlFiles.iterator(); iter.hasNext();) {
-      File xmlFile = iter.next();
+    long lastModified = 0;
+    for (File xmlFile : gwtXmlFiles) {
       if (xmlFile.exists()) {
-        lastModified = Math.min(lastModified, xmlFile.lastModified());
+        lastModified = Math.max(lastModified, xmlFile.lastModified());
       }
     }
-    return lastModified;
+    return lastModified > 0 ? lastModified : moduleDefCreationTime;
   }
 
   /**