Have each SandboxedProcessLauncherDelegate maintain a zygote.

content/public/browser/zygote_host_linux.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_PUBLIC_BROWSER_ZYGOTE_HOST_LINUX_H_
 #define CONTENT_PUBLIC_BROWSER_ZYGOTE_HOST_LINUX_H_
 
 #include <unistd.h>
 
+#include <cstddef>
+
 #include "base/process/process.h"
 #include "content/common/content_export.h"
 
 namespace content {
 
+#if defined(OS_LINUX)

[mdempsky, 2016/01/15 20:29:42]

I think these should go into a new content/public/browser/zygote_handle.h
header, otherwise there will be a compile error due to duplicate type
definitions if you try to include zygote_host_linux.h and
sandboxed_process_launcher_delegate.h in the same .cc file.

Also, this #if condition needs to be defined(OS_POSIX) && !defined(OS_MACOSX) &&
!defined(OS_ANDROID) like all the other Zygote-related stuff.

[Greg K, 2016/01/19 19:34:19]

Done.

+class ZygoteCommunication;
+using ZygoteHandle = ZygoteCommunication*;
+#else
+using ZygoteHandle = std::nullptr_t;
+#endif
+
 // http://code.google.com/p/chromium/wiki/LinuxZygote
 
-// The zygote host is the interface, in the browser process, to the zygote
+// The zygote host is an interface, in the browser process, to the zygote
 // process.
 class ZygoteHost {
  public:
   // Returns the singleton instance.
   CONTENT_EXPORT static ZygoteHost* GetInstance();
 
+  // Allocates and initializes a zygote process, and returns the
+  // ZygoteHandle used to communicate with it.
+  CONTENT_EXPORT static ZygoteHandle CreateZygote();
+
   virtual ~ZygoteHost() {}
 
   // Returns the pid of the Zygote process.
-  virtual pid_t GetPid() const = 0;
+  virtual bool IsZygotePid(pid_t pid) = 0;
 
   // Returns an int which is a bitmask of kSandboxLinux* values. Only valid
   // after the first render has been forked.
-  virtual int GetSandboxStatus() const = 0;
+  virtual int GetRendererSandboxStatus() const = 0;
 
   // Adjust the OOM score of the given renderer's PID.  The allowed
   // range for the score is [0, 1000], where higher values are more
   // likely to be killed by the OOM killer.
   virtual void AdjustRendererOOMScore(base::ProcessHandle process_handle,
                                       int score) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_ZYGOTE_HOST_LINUX_H_