Revert of Linux Sandbox: move init processes to new session id.

content/zygote/zygote_main_linux.cc

 // 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.
 
 #include "content/zygote/zygote_main.h"
 
 #include <dlfcn.h>
 #include <fcntl.h>
 #include <pthread.h>
 #include <signal.h>
@@ skipping 399 matching lines @@
   // be enabled by the process later.
 
   if (!setuid_sandbox->IsSuidSandboxUpToDate()) {
     LOG(WARNING) <<
         "You are using a wrong version of the setuid binary!\n"
         "Please read "
         "https://code.google.com/p/chromium/wiki/LinuxSUIDSandboxDevelopment."
         "\n\n";
   }
 
-  CHECK(setuid_sandbox->CreateNewSession());
-
   if (!setuid_sandbox->ChrootMe())
     return false;
 
   if (setuid_sandbox->IsInNewPIDNamespace()) {
     CHECK_EQ(1, getpid())
         << "The SUID sandbox created a new PID namespace but Zygote "
            "is not the init process. Please, make sure the SUID "
            "binary is up to date.";
   }
 
@@ skipping 210 matching lines @@
   bool setuid_sandbox_engaged = sandbox_flags & kSandboxLinuxSUID;
   CHECK_EQ(must_enable_setuid_sandbox, setuid_sandbox_engaged);
 
   Zygote zygote(sandbox_flags, fork_delegates.Pass(), extra_children,
                 extra_fds);
   // This function call can return multiple times, once per fork().
   return zygote.ProcessRequests();
 }
 
 }  // namespace content