JRE-953 Focus goes behind 'Replace in Path' / "Find in path" dialogs  Review improvements

NPE
diff --git a/src/macosx/classes/sun/lwawt/LWWindowPeer.java b/src/macosx/classes/sun/lwawt/LWWindowPeer.java
index 7e5b693..8c912ec 100644
--- a/src/macosx/classes/sun/lwawt/LWWindowPeer.java
+++ b/src/macosx/classes/sun/lwawt/LWWindowPeer.java
@@ -1333,7 +1333,8 @@
             // 2. Save the window as a previously focused
             previouslyFocusedWindow = focusedWindow;
         } else if (becomesFocused && previouslyFocusedWindow != null) {
-            if (((LWWindowPeer)previouslyFocusedWindow.getPeer()).focusAllowedFor()) {
+          LWWindowPeer focusedWindowPeer = (LWWindowPeer)previouslyFocusedWindow.getPeer();
+          if (focusedWindowPeer != null && focusedWindowPeer.focusAllowedFor()) {
                 // 3. Use the previous focused window
                 eventWindow = previouslyFocusedWindow;
             }