Move base::WeakPtr's null ctor out-of-line

base/memory/weak_ptr.cc

 // 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 "base/memory/weak_ptr.h"
 
 #include "base/debug/leak_annotations.h"
 
 namespace base {
 namespace internal {
@@ skipping 53 matching lines @@
     flag_ = new WeakReference::Flag();
 
   return WeakReference(flag_.get());
 }
 
 void WeakReferenceOwner::Invalidate() {
   flag_->Invalidate();
   flag_ = WeakReference::Flag::NullFlag();
 }
 
-WeakPtrBase::WeakPtrBase() {
-}
+WeakPtrBase::WeakPtrBase() : ptr_(0) {}
 
-WeakPtrBase::~WeakPtrBase() {
-}
+WeakPtrBase::~WeakPtrBase() {}
 
-WeakPtrBase::WeakPtrBase(const WeakReference& ref) : ref_(ref) {
-}
+WeakPtrBase::WeakPtrBase(const WeakReference& ref, uintptr_t ptr)
+    : ref_(ref), ptr_(ptr) {}
 
 WeakPtrFactoryBase::WeakPtrFactoryBase(uintptr_t ptr) : ptr_(ptr) {}
 
 WeakPtrFactoryBase::~WeakPtrFactoryBase() {
   ptr_ = 0;
 }
 
 }  // namespace internal
 }  // namespace base