[ONOS-4910, ONOS-4921] Framework: utils validation and defect fix

Change-Id: I821920fa8c88e64406b702c2b8736bdeaf231474
diff --git a/utils/yangutils/plugin/src/test/resources/default/DefaultInvalidValueEnumerationInLeaf.yang b/utils/yangutils/plugin/src/test/resources/default/DefaultInvalidValueEnumerationInLeaf.yang
new file mode 100644
index 0000000..643dac3
--- /dev/null
+++ b/utils/yangutils/plugin/src/test/resources/default/DefaultInvalidValueEnumerationInLeaf.yang
@@ -0,0 +1,16 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+
+     leaf myenum {
+         type enumeration {
+             enum zero;
+             enum one;
+             enum seven {
+                 value 7;
+             }
+         }
+         default "xyz";
+     }
+}