Don't switch to email as identifier after calling updateEmail with userId

Author: vbabenkoru

iterableapi/src/main/java/com/iterable/iterableapi/IterableApi.java

@@ -753,7 +753,9 @@ public void updateEmail(final String newEmail, final IterableHelper.SuccessHandl
             sendPostRequest(IterableConstants.ENDPOINT_UPDATE_EMAIL, requestJSON, new IterableHelper.SuccessHandler() {
                 @Override
                 public void onSuccess(JSONObject data) {
-                    _email = newEmail;
+                    if (_email != null) {
+                        _email = newEmail;
+                    }
                     storeEmailAndUserId();
                     if (successHandler != null) {
                         successHandler.onSuccess(data);

iterableapi/src/test/java/com/iterable/iterableapi/IterableApiTest.java

@@ -168,6 +168,8 @@ public void testUpdateEmailWithUserId() throws Exception {
         JSONObject requestJson = new JSONObject(updateEmailRequest.getBody().readUtf8());
         assertEquals("testUserId", requestJson.getString(IterableConstants.KEY_CURRENT_USERID));
         assertEquals("[email protected]", requestJson.getString(IterableConstants.KEY_NEW_EMAIL));
+        assertNull(IterableApi.getInstance().getEmail());
+        assertEquals("testUserId", IterableApi.getInstance().getUserId());
     }
 
     @Test