[Mac] Remove the dedicated MachBroker thread and use a dispatch queue instead.

content/browser/mach_broker_mac.h

 // 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.
 
 #ifndef CONTENT_BROWSER_MACH_BROKER_MAC_H_
 #define CONTENT_BROWSER_MACH_BROKER_MAC_H_
 
 #include <mach/mach.h>
 
 #include <map>
 #include <string>
 
+#include "base/mac/dispatch_source_mach.h"
+#include "base/mac/scoped_mach_port.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "base/process/process_handle.h"
 #include "base/process/process_metrics.h"
 #include "base/synchronization/lock.h"
 #include "content/public/browser/browser_child_process_observer.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 namespace content {
 
@@ skipping 49 matching lines @@
   void BrowserChildProcessCrashed(const ChildProcessData& data,
       int exit_code) override;
 
   // Implement |NotificationObserver|.
   void Observe(int type,
                const NotificationSource& source,
                const NotificationDetails& details) override;
 
  private:
   friend class MachBrokerTest;
-  friend class MachListenerThreadDelegate;
   friend struct DefaultSingletonTraits<MachBroker>;
 
   MachBroker();
   ~MachBroker() override;
 
+  // Performs any initialization work.
+  bool Init();
+
+  // Message handler that is invoked on |dispatch_source_| when an
+  // incoming message needs to be received.
+  void HandleRequest();
+
   // Updates the mapping for |pid| to include the given |mach_info|.  Does
   // nothing if PlaceholderForPid() has not already been called for the given
   // |pid|.  Callers MUST acquire the lock given by GetLock() before calling
   // this method (and release the lock afterwards).
   void FinalizePid(base::ProcessHandle pid, mach_port_t task_port);
 
   // Removes all mappings belonging to |child_process_id| from the broker.
   void InvalidateChildProcessId(int child_process_id);
 
   // Returns the Mach port name to use when sending or receiving messages.
   // Does the Right Thing in the browser and in child processes.
   static std::string GetMachPortName();
+
   // Callback used to register notifications on the UI thread.
   void RegisterNotifications();
 
-  // True if the listener thread has been started.
-  bool listener_thread_started_;
+  // Whether or not the class has been initialized.
+  bool initialized_;
 
   // Used to register for notifications received by NotificationObserver.
   // Accessed only on the UI thread.
   NotificationRegistrar registrar_;
 
+  // The Mach port on which the server listens.
+  base::mac::ScopedMachReceiveRight server_port_;
+
+  // The dispatch source and queue on which Mach messages will be received.
+  scoped_ptr<base::DispatchSourceMach> dispatch_source_;
+
   // Stores mach info for every process in the broker.
   typedef std::map<base::ProcessHandle, mach_port_t> MachMap;
   MachMap mach_map_;
 
   // Stores the Child process unique id (RenderProcessHost ID) for every
   // process.
   typedef std::map<int, base::ProcessHandle> ChildProcessIdMap;
   ChildProcessIdMap child_process_id_map_;
 
   // Mutex that guards |mach_map_| and |child_process_id_map_|.
   mutable base::Lock lock_;
 
   DISALLOW_COPY_AND_ASSIGN(MachBroker);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_MACH_BROKER_MAC_H_