Add PDF compositor service

content/public/child/child_thread.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_CHILD_CHILD_THREAD_H_
 #define CONTENT_PUBLIC_CHILD_CHILD_THREAD_H_
 
 #include <string>
 
-#include "base/logging.h"
+#include "base/memory/ref_counted.h"
 #include "build/build_config.h"
 #include "content/common/content_export.h"
 #include "ipc/ipc_sender.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 
 namespace base {
+class SingleThreadTaskRunner;
 struct UserMetricsAction;
 }
 
 namespace service_manager {
 class Connector;
 }
 
 namespace content {
 
 class ServiceManagerConnection;
@@ skipping 36 matching lines @@
   // actions in chrome/tools/extract_actions.py.
   virtual void RecordComputedAction(const std::string& action) = 0;
 
   // Returns the ServiceManagerConnection for the thread (from which a
   // service_manager::Connector can be obtained).
   virtual ServiceManagerConnection* GetServiceManagerConnection() = 0;
 
   // Returns a connector that can be used to bind interfaces exposed by other
   // services.
   virtual service_manager::Connector* GetConnector() = 0;
+
+  virtual scoped_refptr<base::SingleThreadTaskRunner> GetIOTaskRunner() = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_CHILD_CHILD_THREAD_H_