ipc: Move AttachmentBrokerPrivileged singleton logic into ipc/.

ipc/attachment_broker.cc

 // 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.
 
 #include "ipc/attachment_broker.h"
 
 #include <algorithm>
 
 namespace {
 IPC::AttachmentBroker* g_attachment_broker = nullptr;
 }
 
 namespace IPC {
 
 // static
 void AttachmentBroker::SetGlobal(AttachmentBroker* broker) {
   CHECK(!g_attachment_broker || !broker)
       << "Global attachment broker address: " << broker
       << ". New attachment broker address: " << broker;
   g_attachment_broker = broker;
 }
 
 // static
 AttachmentBroker* AttachmentBroker::GetGlobal() {
   return g_attachment_broker;
 }
 
-#if defined(OS_MACOSX) && !defined(OS_IOS)
-AttachmentBroker::AttachmentBroker() : port_provider_(nullptr) {}
-#else
 AttachmentBroker::AttachmentBroker() {}
-#endif  // defined(OS_MACOSX) && !defined(OS_IOS)
-
 AttachmentBroker::~AttachmentBroker() {}
 
 bool AttachmentBroker::GetAttachmentWithId(
     BrokerableAttachment::AttachmentId id,
     scoped_refptr<BrokerableAttachment>* out_attachment) {
   for (AttachmentVector::iterator it = attachments_.begin();
        it != attachments_.end(); ++it) {
     if ((*it)->GetIdentifier() == id) {
       *out_attachment = *it;
       attachments_.erase(it);
@@ skipping 32 matching lines @@
 void AttachmentBroker::NotifyObservers(
     const BrokerableAttachment::AttachmentId& id) {
   // Make a copy of observers_ to avoid mutations during iteration.
   std::vector<Observer*> observers = observers_;
   for (Observer* observer : observers) {
     observer->ReceivedBrokerableAttachmentWithId(id);
   }
 }
 
 }  // namespace IPC