content: Increase thread priority for display critical IO threads on ChromeOS.

content/child/child_process.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_CHILD_CHILD_PROCESS_H_
 #define CONTENT_CHILD_CHILD_PROCESS_H_
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/waitable_event.h"
@@ skipping 15 matching lines @@
 //   4. IO thread is stopped.
 // 5. Main message loop exits.
 // 6. Child process is now fully stopped.
 //
 // Note: IO thread outlives the ChildThreadImpl object.
 class CONTENT_EXPORT ChildProcess {
  public:
   // Child processes should have an object that derives from this class.
   // Normally you would immediately call set_main_thread after construction.
   ChildProcess();
+  explicit ChildProcess(base::ThreadPriority io_thread_priority);
   virtual ~ChildProcess();
 
   // May be NULL if the main thread hasn't been set explicitly.
   ChildThreadImpl* main_thread();
 
   // Sets the object associated with the main thread of this process.
   // Takes ownership of the pointer.
   void set_main_thread(ChildThreadImpl* thread);
 
   base::MessageLoop* io_message_loop() { return io_thread_.message_loop(); }
@@ skipping 36 matching lines @@
   // it depends on it (indirectly through IPC::SyncChannel).  Same for
   // io_thread_.
   scoped_ptr<ChildThreadImpl> main_thread_;
 
   DISALLOW_COPY_AND_ASSIGN(ChildProcess);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_CHILD_CHILD_PROCESS_H_