Add const to BindStateBase to align RefCounted constness

base/callback_unittest.cc

 // Copyright (c) 2012 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.
 
 #include "base/callback.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/callback_internal.h"
 #include "base/memory/ref_counted.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
 
 void NopInvokeFunc() {}
 
 // White-box testpoints to inject into a Callback<> object for checking
 // comparators and emptiness APIs.  Use a BindState that is specialized
 // based on a type we declared in the anonymous namespace above to remove any
 // chance of colliding with another instantiation and breaking the
 // one-definition-rule.
 struct FakeBindState1 : internal::BindStateBase {
   FakeBindState1() : BindStateBase(&NopInvokeFunc, &Destroy, &IsCancelled) {}
  private:
   ~FakeBindState1() {}
-  static void Destroy(internal::BindStateBase* self) {
-    delete static_cast<FakeBindState1*>(self);
+  static void Destroy(const internal::BindStateBase* self) {
+    delete static_cast<const FakeBindState1*>(self);
   }
   static bool IsCancelled(const internal::BindStateBase*) {
     return false;
   }
 };
 
 struct FakeBindState2 : internal::BindStateBase {
   FakeBindState2() : BindStateBase(&NopInvokeFunc, &Destroy, &IsCancelled) {}
  private:
   ~FakeBindState2() {}
-  static void Destroy(internal::BindStateBase* self) {
-    delete static_cast<FakeBindState2*>(self);
+  static void Destroy(const internal::BindStateBase* self) {
+    delete static_cast<const FakeBindState2*>(self);
   }
   static bool IsCancelled(const internal::BindStateBase*) {
     return false;
   }
 };
 
 namespace {
 
 class CallbackTest : public ::testing::Test {
  public:
@@ skipping 111 matching lines @@
 
 TEST_F(CallbackTest, CallbackHasLastRefOnContainingObject) {
   bool deleted = false;
   CallbackOwner* owner = new CallbackOwner(&deleted);
   owner->Reset();
   ASSERT_TRUE(deleted);
 }
 
 }  // namespace
 }  // namespace base