added a method to detect multi-line string. Used in views.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@1917 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/Functions.java

@@ -307,4 +307,8 @@ public class Functions {
     public static String getWin32ErrorMessage(IOException e) {
         return Util.getWin32ErrorMessage(e);
     }
+
+    public static boolean isMultiline(String s) {
+        return s.indexOf('\r')>=0 || s.indexOf('\n')>=0;
+    }
 }