EDK: Sprinkle some more |final| secret sauce.

mojo/edk/util/ref_ptr.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Provides a smart pointer class for intrusively reference-counted objects.
 
 #ifndef MOJO_EDK_UTIL_REF_PTR_H_
 #define MOJO_EDK_UTIL_REF_PTR_H_
 
 #include <assert.h>
@@ skipping 45 matching lines @@
 // |U = T|, since the templated versions don't count as copy/move
 // constructors/operator=s for the purposes of causing the default copy
 // constructor/operator= to be deleted. E.g., if we didn't declare any
 // non-templated versions, we'd get the default copy constructor/operator= (we'd
 // only not get the default move constructor/operator= by virtue of having a
 // destructor)! (In fact, it'd suffice to only declare a non-templated move
 // constructor or move operator=, which would cause the copy
 // constructor/operator= to be deleted, but for clarity we include explicit
 // non-templated versions of everything.)
 template <typename T>
-class RefPtr {
+class RefPtr final {
  public:
   RefPtr() : ptr_(nullptr) {}
   RefPtr(std::nullptr_t) : ptr_(nullptr) {}
 
   // Explicit constructor from a plain pointer (to an object that must have
   // already been adopted). (Note that in |T::T()|, references to |this| cannot
   // be taken, since the object being constructed will not have been adopted
   // yet.)
   template <typename U>
   explicit RefPtr(U* p)
@@ skipping 147 matching lines @@
 template <typename T, typename... Args>
 RefPtr<T> MakeRefCounted(Args&&... args) {
   return internal::MakeRefCountedHelper<T>::MakeRefCounted(
       std::forward<Args>(args)...);
 }
 
 }  // namespace util
 }  // namespace mojo
 
 #endif  // MOJO_EDK_UTIL_REF_PTR_H_