Add missing test from jetty-7

jetty-webapp/src/test/java/org/eclipse/jetty/webapp/WebAppContextTest.java

@@ -87,6 +87,24 @@ public class WebAppContextTest
         assertTrue(Arrays.equals(configs,wac.getConfigurations()));
     }
     
+    @Test
+    public void testRealPathDoesNotExist() throws Exception
+    {
+        Server server = new Server(0);
+        WebAppContext context = new WebAppContext(".", "/");
+        server.setHandler(context);
+        server.start();
+
+        // When
+        ServletContext ctx = context.getServletContext();
+
+        // Then
+        // This passes:
+        assertNotNull(ctx.getRealPath("/doesnotexist"));
+        // This fails:
+        assertNotNull(ctx.getRealPath("/doesnotexist/"));
+    }
+    
     /**
      * tests that the servlet context white list works
      *