Have each SandboxedProcessLauncherDelegate maintain a zygote.

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index 83a4bd7d7381b6d11fd7cbfb095cdc3d0764e94c..e6f9e175d1602730bdd178b7a877417fdb2b8f43 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -200,6 +200,11 @@
 #include "content/browser/mach_broker_mac.h"
 #endif
 
+#if defined(OS_POSIX)
+#include "content/browser/zygote_host/zygote_communication_linux.h"
+#include "content/browser/zygote_host/zygote_host_impl_linux.h"
+#endif  // defined(OS_POSIX)
+
 #if defined(USE_OZONE)
 #include "ui/ozone/public/client_native_pixmap_factory.h"
 #include "ui/ozone/public/ozone_platform.h"
@@ -388,13 +393,28 @@ class RendererSandboxedProcessLauncherDelegate
   }
 
 #elif defined(OS_POSIX)
-  bool ShouldUseZygote() override {
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
+  ZygoteHandle* GetZygote() override {
     const base::CommandLine& browser_command_line =
         *base::CommandLine::ForCurrentProcess();
     base::CommandLine::StringType renderer_prefix =
         browser_command_line.GetSwitchValueNative(switches::kRendererCmdPrefix);
-    return renderer_prefix.empty();
+    if (!renderer_prefix.empty())
+      return nullptr;
+
+    static ZygoteHandle zygote;
+    if (zygote == nullptr) {
+      zygote = new ZygoteCommunication();
+      zygote->Init();
+      // TODO(kerrnel): Investigate doing this without the ZygoteHostImpl as a
+      // proxy. It is currently done this way due to concerns about race
+      // conditions.
+      ZygoteHostImpl::GetInstance()->SetRendererSandboxStatus(
+          zygote->GetSandboxStatus());
+    }
+    return &zygote;
   }
+#endif  // !defined(OS_MACOSX) && !defined(OS_ANDROID)
   base::ScopedFD TakeIpcFd() override { return std::move(ipc_fd_); }
 #endif  // OS_WIN