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/JS_Object.cpp b/fpdfsdk/src/javascript/JS_Object.cpp
index 96e1d1d..0297898 100644
--- a/fpdfsdk/src/javascript/JS_Object.cpp
+++ b/fpdfsdk/src/javascript/JS_Object.cpp
@@ -89,7 +89,7 @@
   m_pObject.Reset(m_pIsolate, pObject);
 };
 
-CJS_Object::~CJS_Object(void) {
+CJS_Object::~CJS_Object() {
   m_pObject.Reset();
 };