Make BindStateBase RefCountedThreadSafe

base/callback_internal.cc

Index: base/callback_internal.cc
diff --git a/base/callback_internal.cc b/base/callback_internal.cc
index 4afd567f0fe32ee65c911f8a1cf55c061c7b95c3..9de164fb0585da433af2fb480df2724757ccb67d 100644
--- a/base/callback_internal.cc
+++ b/base/callback_internal.cc
@@ -17,6 +17,11 @@ bool ReturnFalse(const BindStateBase*) {
 
 }  // namespace
 
+// static
+void BindStateBaseRefCountTraits::Destruct(const BindStateBase* obj) {
+  obj->destructor_(obj);
+}
+
 BindStateBase::BindStateBase(InvokeFuncStorage polymorphic_invoke,
                              void (*destructor)(const BindStateBase*))
     : BindStateBase(polymorphic_invoke, destructor, &ReturnFalse) {
@@ -26,19 +31,9 @@ BindStateBase::BindStateBase(InvokeFuncStorage polymorphic_invoke,
                              void (*destructor)(const BindStateBase*),
                              bool (*is_cancelled)(const BindStateBase*))
     : polymorphic_invoke_(polymorphic_invoke),
-      ref_count_(0),
       destructor_(destructor),
       is_cancelled_(is_cancelled) {}
 
-void BindStateBase::AddRef() const {
-  AtomicRefCountInc(&ref_count_);
-}
-
-void BindStateBase::Release() const {
-  if (!AtomicRefCountDec(&ref_count_))
-    destructor_(this);
-}
-
 CallbackBase<CopyMode::MoveOnly>::CallbackBase(CallbackBase&& c) = default;
 
 CallbackBase<CopyMode::MoveOnly>&
@@ -73,7 +68,7 @@ bool CallbackBase<CopyMode::MoveOnly>::EqualsInternal(
 CallbackBase<CopyMode::MoveOnly>::CallbackBase(
     BindStateBase* bind_state)
     : bind_state_(bind_state) {
-  DCHECK(!bind_state_.get() || bind_state_->ref_count_ == 1);
+  DCHECK(!bind_state_.get() || bind_state_->HasOneRef());
 }
 
 CallbackBase<CopyMode::MoveOnly>::~CallbackBase() {}