Return result message for the user who uploaded the proto message file

Test: go/vts-web-staging
Bug: 119160910
Change-Id: I8346cd80a7a74baec9f2d5a649f198dcf9ee0fec
diff --git a/src/main/java/com/android/vts/api/CoverageRestServlet.java b/src/main/java/com/android/vts/api/CoverageRestServlet.java
index 165db8d..aebd3e5 100644
--- a/src/main/java/com/android/vts/api/CoverageRestServlet.java
+++ b/src/main/java/com/android/vts/api/CoverageRestServlet.java
@@ -106,10 +106,8 @@
         List<List<String>> allCoveredHalApiList = new ArrayList();
 
         Key<TestPlanRunEntity> key = Key.create(urlSafeKey);
-        System.out.println("urlSafekey => " + urlSafeKey);
         TestPlanRunEntity testPlanRunEntity = ofy().load().key(key).safe();
 
-        System.out.println("testPlanRunEntity => " + testPlanRunEntity);
         for (Key<TestRunEntity> testRunKey : testPlanRunEntity.getTestRuns()) {
             List<ApiCoverageEntity> apiCoverageEntityList =
                     ofy().load().type(ApiCoverageEntity.class).ancestor(testRunKey).list();
diff --git a/src/main/java/com/android/vts/api/DatastoreRestServlet.java b/src/main/java/com/android/vts/api/DatastoreRestServlet.java
index 5ddf18d..fb5ac65 100644
--- a/src/main/java/com/android/vts/api/DatastoreRestServlet.java
+++ b/src/main/java/com/android/vts/api/DatastoreRestServlet.java
@@ -87,6 +87,7 @@
             return;
         }
 
+        String resultMsg = "";
         // Verify service account access token.
         if (postMessage.hasAccessToken()) {
             String accessToken = postMessage.getAccessToken();
@@ -109,15 +110,21 @@
                 }
 
                 response.setStatus(HttpServletResponse.SC_OK);
+                resultMsg = "Success!!";
             } else {
                 log.warn("service_client_id didn't match!");
                 log.debug("SERVICE_CLIENT_ID => " + tokenInfo.getIssuedTo());
+                resultMsg = "Your SERVICE_CLIENT_ID is incorrect!";
                 response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
             }
         } else {
             log.error("postMessage do not contain any accessToken!");
+            resultMsg = "Your message do not have access token!";
             response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
         }
+        response.setContentType("application/json");
+        response.setCharacterEncoding("UTF-8");
+        response.getWriter().write("{'result_msg': " + resultMsg + "}");
     }
 
     /**
@@ -446,13 +453,6 @@
         Map<com.googlecode.objectify.Key<TestRunEntity>, TestRunEntity> testRunEntityMap =
                 ofy().load().keys(() -> testRunKeyList.iterator());
 
-        testRunKeyList.forEach(
-                (v) -> {
-                    log.debug("TestRunEntity key value => " + v);
-                });
-        log.debug("testRunEntityMap value => " + testRunEntityMap.values());
-        log.debug("testRunEntityMap keySet => " + testRunEntityMap.keySet());
-
         long passCount = 0;
         long failCount = 0;
         long startTimestamp = -1;