8049996: [macosx] test java/awt/image/ImageIconHang.java fails with NPE

Reviewed-by: alexsch, azvegint
diff --git a/jdk/src/macosx/classes/sun/lwawt/macosx/LWCToolkit.java b/jdk/src/macosx/classes/sun/lwawt/macosx/LWCToolkit.java
index e0e07f0..86b65a0 100644
--- a/jdk/src/macosx/classes/sun/lwawt/macosx/LWCToolkit.java
+++ b/jdk/src/macosx/classes/sun/lwawt/macosx/LWCToolkit.java
@@ -538,9 +538,9 @@
             return super.getImage(filename);
         }
 
-        String fileneame2x = getScaledImageName(filename);
-        return (imageExists(fileneame2x))
-                ? getImageWithResolutionVariant(filename, fileneame2x)
+        String filename2x = getScaledImageName(filename);
+        return (imageExists(filename2x))
+                ? getImageWithResolutionVariant(filename, filename2x)
                 : super.getImage(filename);
     }
 
@@ -891,6 +891,9 @@
     }
 
     private static boolean isValidPath(String path) {
-        return !path.isEmpty() && !path.endsWith("/") && !path.endsWith(".");
+        return path != null &&
+                !path.isEmpty() &&
+                !path.endsWith("/") &&
+                !path.endsWith(".");
     }
 }