Revert of Have each SandboxedProcessLauncherDelegate maintain a zygote.

content/browser/ppapi_plugin_process_host.cc

Index: content/browser/ppapi_plugin_process_host.cc
diff --git a/content/browser/ppapi_plugin_process_host.cc b/content/browser/ppapi_plugin_process_host.cc
index 7932b86f9e90d067df66895b490fcfa10df7fe8a..1817c762d239b812fe1193dd63223d127a4a5b0d 100644
--- a/content/browser/ppapi_plugin_process_host.cc
+++ b/content/browser/ppapi_plugin_process_host.cc
@@ -35,10 +35,6 @@
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ui/base/ui_base_switches.h"
 
-#if defined(OS_POSIX)
-#include "content/public/browser/zygote_handle_linux.h"
-#endif  // defined(OS_POSIX)
-
 #if defined(OS_WIN)
 #include "content/browser/renderer_host/dwrite_font_proxy_message_filter_win.h"
 #include "content/common/sandbox_win.h"
@@ -48,10 +44,6 @@
 #endif
 
 namespace content {
-
-#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
-ZygoteHandle g_ppapi_zygote;
-#endif  // defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
 
 // NOTE: changes to this class need to be reviewed by the security team.
 class PpapiPluginSandboxedProcessLauncherDelegate
@@ -105,18 +97,13 @@
   }
 
 #elif defined(OS_POSIX)
-#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
-  ZygoteHandle* GetZygote() override {
+  bool ShouldUseZygote() override {
     const base::CommandLine& browser_command_line =
         *base::CommandLine::ForCurrentProcess();
     base::CommandLine::StringType plugin_launcher = browser_command_line
         .GetSwitchValueNative(switches::kPpapiPluginLauncher);
-    if (is_broker_ || !plugin_launcher.empty())
-      return nullptr;
-    return &g_ppapi_zygote;
-  }
-#endif  // !defined(OS_MACOSX) && !defined(OS_ANDROID)
-
+    return !is_broker_ && plugin_launcher.empty();
+  }
   base::ScopedFD TakeIpcFd() override { return std::move(ipc_fd_); }
 #endif  // OS_WIN
 
@@ -202,14 +189,6 @@
   NOTREACHED();  // Init is not expected to fail.
   return NULL;
 }
-
-#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
-// static
-void PpapiPluginProcessHost::EarlyZygoteLaunch() {
-  DCHECK(!g_ppapi_zygote);
-  g_ppapi_zygote = CreateZygote();
-}
-#endif  // defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
 
 // static
 void PpapiPluginProcessHost::DidCreateOutOfProcessInstance(