Use SharedPersistentMemoryAllocator to share field trial state

content/browser/child_process_launcher.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_CHILD_PROCESS_LAUNCHER_H_
 #define CONTENT_BROWSER_CHILD_PROCESS_LAUNCHER_H_
 
 #include "base/files/scoped_file.h"
 #include "base/macros.h"
 #include "base/memory/shared_memory.h"
@@ skipping 62 matching lines @@
   // Takes ownership of cmd_line.
   //
   // If |process_error_callback| is provided, it will be called if a Mojo error
   // is encountered when processing messages from the child process. This
   // callback must be safe to call from any thread.
   ChildProcessLauncher(
       SandboxedProcessLauncherDelegate* delegate,
       base::CommandLine* cmd_line,
       int child_process_id,
       Client* client,
-      const base::SharedMemory* field_trial_state,
       const std::string& mojo_child_token,
       const mojo::edk::ProcessErrorCallback& process_error_callback,
       bool terminate_on_shutdown = true);
   ~ChildProcessLauncher();
 
   // True if the process is being launched and so the handle isn't available.
   bool IsStarting();
 
   // Getter for the process.  Only call after the process has started.
   const base::Process& GetProcess() const;
@@ skipping 17 matching lines @@
   void SetProcessBackgrounded(bool background);
 
   // Replaces the ChildProcessLauncher::Client for testing purposes. Returns the
   // previous  client.
   Client* ReplaceClientForTest(Client* client);
 
  private:
   // Posts a task to the launcher thread to do the actual work.
   void Launch(SandboxedProcessLauncherDelegate* delegate,
               base::CommandLine* cmd_line,
-              int child_process_id,
-              const base::SharedMemory* field_trial_state);
+              int child_process_id);
 
   void UpdateTerminationStatus(bool known_dead);
 
   // This is always called on the client thread after an attempt
   // to launch the child process on the launcher thread.
   // It makes sure we always perform the necessary cleanup if the
   // client went away.
   static void DidLaunch(base::WeakPtr<ChildProcessLauncher> instance,
                         bool terminate_on_shutdown,
                         mojo::edk::ScopedPlatformHandle server_handle,
@@ skipping 30 matching lines @@
   const std::string mojo_child_token_;
 
   base::WeakPtrFactory<ChildProcessLauncher> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChildProcessLauncher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_CHILD_PROCESS_LAUNCHER_H_