MdeModulePkg: Add submitted callback test case in DriverSample

Now we add new HII action type EFI_BROWSER_ACTION_SUBMITTED in
EFI HII Configuration Access Protocol, so add the test case in
DriverSample to show how to use it and whether it works.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

MdeModulePkg/Universal/DriverSampleDxe/DriverSample.c

@@ -2,7 +2,7 @@
 This is an example of how a driver might export data to the HII protocol to be
 later utilized by the Setup Protocol
 
-Copyright (c) 2004 - 2015, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2004 - 2016, Intel Corporation. All rights reserved.<BR>
 This program and the accompanying materials
 are licensed and made available under the terms and conditions of the BSD License
 which accompanies this distribution.  The full text of the license may be found at
@@ -1834,6 +1834,28 @@ DriverCallback (
     }
   break;
 
+  case EFI_BROWSER_ACTION_SUBMITTED:
+    {
+      if (QuestionId == 0x1250) {
+        //
+        // Sample CallBack for EFI_BROWSER_ACTION_SUBMITTED action:
+        // Show up a pop-up to show SUBMITTED callback has been triggered.
+        //
+        do {
+          CreatePopUp (
+            EFI_LIGHTGRAY | EFI_BACKGROUND_BLUE,
+            &Key,
+            L"",
+            L"EfiVarstore value has been submitted!",
+            L"Press ESC or ENTER to continue ...",
+            L"",
+            NULL
+            );
+        } while ((Key.ScanCode != SCAN_ESC) && (Key.UnicodeChar != CHAR_CARRIAGE_RETURN));
+      }
+    }
+    break;
+
   default:
     Status = EFI_UNSUPPORTED;
     break;