Merge to XFA: Use override in more classes in fpdfsdk/

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1287193005 .

(cherry picked from commit 0f6b51c0fdd14f5762bf3c7412ac59c825443cc3)

Review URL: https://codereview.chromium.org/1288393004 .
diff --git a/fpdfsdk/src/javascript/util.cpp b/fpdfsdk/src/javascript/util.cpp
index c735b97..85092da 100644
--- a/fpdfsdk/src/javascript/util.cpp
+++ b/fpdfsdk/src/javascript/util.cpp
@@ -48,7 +48,8 @@
 
 util::util(CJS_Object* pJSObject) : CJS_EmbedObj(pJSObject) {}
 
-util::~util(void) {}
+util::~util() {
+}
 
 struct stru_TbConvert {
   const FX_WCHAR* lpszJSMark;