Create 2272 release branch for CEF3.

git-svn-id: https://chromiumembedded.googlecode.com/svn/branches/2272@1993 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef_dll/base/cef_weak_ptr.cc

@@ -0,0 +1,77 @@
+// Copyright (c) 2011 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 "include/base/cef_weak_ptr.h"
+
+namespace base {
+namespace cef_internal {
+
+WeakReference::Flag::Flag() : is_valid_(true) {
+  // Flags only become bound when checked for validity, or invalidated,
+  // so that we can check that later validity/invalidation operations on
+  // the same Flag take place on the same thread.
+  thread_checker_.DetachFromThread();
+}
+
+void WeakReference::Flag::Invalidate() {
+  // The flag being invalidated with a single ref implies that there are no
+  // weak pointers in existence. Allow deletion on other thread in this case.
+  DCHECK(thread_checker_.CalledOnValidThread() || HasOneRef())
+      << "WeakPtrs must be invalidated on the same thread.";
+  is_valid_ = false;
+}
+
+bool WeakReference::Flag::IsValid() const {
+  DCHECK(thread_checker_.CalledOnValidThread())
+      << "WeakPtrs must be checked on the same thread.";
+  return is_valid_;
+}
+
+WeakReference::Flag::~Flag() {
+}
+
+WeakReference::WeakReference() {
+}
+
+WeakReference::WeakReference(const Flag* flag) : flag_(flag) {
+}
+
+WeakReference::~WeakReference() {
+}
+
+bool WeakReference::is_valid() const { return flag_.get() && flag_->IsValid(); }
+
+WeakReferenceOwner::WeakReferenceOwner() {
+}
+
+WeakReferenceOwner::~WeakReferenceOwner() {
+  Invalidate();
+}
+
+WeakReference WeakReferenceOwner::GetRef() const {
+  // If we hold the last reference to the Flag then create a new one.
+  if (!HasRefs())
+    flag_ = new WeakReference::Flag();
+
+  return WeakReference(flag_.get());
+}
+
+void WeakReferenceOwner::Invalidate() {
+  if (flag_.get()) {
+    flag_->Invalidate();
+    flag_ = NULL;
+  }
+}
+
+WeakPtrBase::WeakPtrBase() {
+}
+
+WeakPtrBase::~WeakPtrBase() {
+}
+
+WeakPtrBase::WeakPtrBase(const WeakReference& ref) : ref_(ref) {
+}
+
+}  // namespace cef_internal
+}  // namespace base