Fix multiple locale showing in login failed page (#2434)

This commit is a further address to the issue #1518

Currently when the selected language is not English in login page, when login failed (e.g the password is incorrect), the login page will return with an English Page.
The commit fix this problem by adding an additional locale parameter to fail method in LoginServlet.java

appinventor/appengine/src/com/google/appinventor/server/LoginServlet.java

@@ -116,7 +116,7 @@ public class LoginServlet extends HttpServlet {
       // This is arranged via a security-constraint setup in web.xml
       com.google.appengine.api.users.User apiUser = userService.getCurrentUser();
       if (apiUser == null) {  // Hmmm. I don't think this should happen
-        fail(req, resp, "Google Authentication Failed"); // Not sure what else to do
+        fail(req, resp, "Google Authentication Failed", locale); // Not sure what else to do
         return;
       }
       String email = apiUser.getEmail();
@@ -184,12 +184,12 @@ public class LoginServlet extends HttpServlet {
     if (page.equals("setpw")) {
       String uid = getParam(req);
       if (uid == null) {
-        fail(req, resp, "Invalid Set Password Link");
+        fail(req, resp, "Invalid Set Password Link", locale);
         return;
       }
       PWData data = storageIo.findPWData(uid);
       if (data == null) {
-        fail(req, resp, "Invalid Set Password Link");
+        fail(req, resp, "Invalid Set Password Link", locale);
         return;
       }
       if (DEBUG) {
@@ -300,13 +300,13 @@ public class LoginServlet extends HttpServlet {
     if (page.equals("sendlink")) {
       String email = params.get("email");
       if (email == null) {
-        fail(req, resp, "No Email Address Provided");
+        fail(req, resp, "No Email Address Provided", locale);
         return;
       }
       // Send email here, for now we put it in the error string and redirect
       PWData pwData = storageIo.createPWData(email);
       if (pwData == null) {
-        fail(req, resp, "Internal Error");
+        fail(req, resp, "Internal Error", locale);
         return;
       }
       String link = trimPage(req) + pwData.id + "/setpw";
@@ -316,23 +316,23 @@ public class LoginServlet extends HttpServlet {
       return;
     } else if (page.equals("setpw")) {
       if (userInfo == null || userInfo.getUserId().equals("")) {
-        fail(req, resp, "Session Timed Out");
+        fail(req, resp, "Session Timed Out", locale);
         return;
       }
       User user = storageIo.getUser(userInfo.getUserId());
       String password = params.get("password");
       if (password == null || password.equals("")) {
-        fail(req, resp, bundle.getString("nopassword"));
+        fail(req, resp, bundle.getString("nopassword"), locale);
         return;
       }
       String hashedPassword;
       try {
         hashedPassword = PasswordHash.createHash(password);
       } catch (NoSuchAlgorithmException e) {
-        fail(req, resp, "System Error hashing password");
+        fail(req, resp, "System Error hashing password", locale);
         return;
       } catch (InvalidKeySpecException e) {
-        fail(req, resp, "System Error hashing password");
+        fail(req, resp, "System Error hashing password", locale);
         return;
       }
 
@@ -354,7 +354,7 @@ public class LoginServlet extends HttpServlet {
 
     String hash = user.getPassword();
     if ((hash == null) || hash.equals("")) {
-      fail(req, resp, "No Password Set for User");
+      fail(req, resp, "No Password Set for User", locale);
       return;
     }
 
@@ -365,7 +365,7 @@ public class LoginServlet extends HttpServlet {
     }
 
     if (!validLogin) {
-      fail(req, resp, bundle.getString("invalidpassword"));
+      fail(req, resp, bundle.getString("invalidpassword"), locale);
       return;
     }
 
@@ -440,8 +440,8 @@ public class LoginServlet extends HttpServlet {
     return sb.toString();
   }
 
-  private void fail(HttpServletRequest req, HttpServletResponse resp, String error) throws IOException {
-    resp.sendRedirect("/login/?error=" + sanitizer.sanitize(error));
+  private void fail(HttpServletRequest req, HttpServletResponse resp, String error, String locale) throws IOException {
+    resp.sendRedirect("/login/?locale=" + sanitizer.sanitize(locale) + "&error=" + sanitizer.sanitize(error));
     return;
   }