Have each SandboxedProcessLauncherDelegate maintain a zygote.

content/browser/utility_process_host_impl.cc

Index: content/browser/utility_process_host_impl.cc
diff --git a/content/browser/utility_process_host_impl.cc b/content/browser/utility_process_host_impl.cc
index db67d60dc225e1c161e818315153975801596476..447685a3382e8310ab61e8c4044c1dc5c34b0d9f 100644
--- a/content/browser/utility_process_host_impl.cc
+++ b/content/browser/utility_process_host_impl.cc
@@ -37,6 +37,10 @@
 #include "ipc/ipc_switches.h"
 #include "ui/base/ui_base_switches.h"
 
+#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
+#include "content/public/browser/zygote_handle_linux.h"
+#endif  // defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
+
 #if defined(OS_WIN)
 #include "sandbox/win/src/sandbox_policy.h"
 #include "sandbox/win/src/sandbox_types.h"
@@ -44,6 +48,12 @@
 
 namespace content {
 
+#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
+namespace {
+ZygoteHandle g_utility_zygote;
+}  // namespace
+#endif  // defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
+
 // NOTE: changes to this class need to be reviewed by the security team.
 class UtilitySandboxedProcessLauncherDelegate
     : public SandboxedProcessLauncherDelegate {
@@ -58,7 +68,9 @@ class UtilitySandboxedProcessLauncherDelegate
         launch_elevated_(launch_elevated)
 #elif defined(OS_POSIX)
         env_(env),
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
         no_sandbox_(no_sandbox),
+#endif  // !defined(OS_MACOSX)  && !defined(OS_ANDROID)
         ipc_fd_(host->TakeClientFileDescriptor())
 #endif  // OS_WIN
   {}
@@ -88,9 +100,13 @@ class UtilitySandboxedProcessLauncherDelegate
 
 #elif defined(OS_POSIX)
 
-  bool ShouldUseZygote() override {
-    return !no_sandbox_ && exposed_dir_.empty();
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
+  ZygoteHandle* GetZygote() override {
+    if (no_sandbox_ || !exposed_dir_.empty())
+      return nullptr;
+    return &g_utility_zygote;
   }
+#endif  // !defined(OS_MACOSX) && !defined(OS_ANDROID)
   base::EnvironmentMap GetEnvironment() override { return env_; }
   base::ScopedFD TakeIpcFd() override { return std::move(ipc_fd_); }
 #endif  // OS_WIN
@@ -106,7 +122,9 @@ class UtilitySandboxedProcessLauncherDelegate
   bool launch_elevated_;
 #elif defined(OS_POSIX)
   base::EnvironmentMap env_;
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
   bool no_sandbox_;
+#endif  // !defined(OS_MACOSX) && !defined(OS_ANDROID)
   base::ScopedFD ipc_fd_;
 #endif  // OS_WIN
 };
@@ -220,6 +238,14 @@ void UtilityProcessHostImpl::SetName(const base::string16& name) {
   name_ = name;
 }
 
+#if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
+// static
+void UtilityProcessHostImpl::EarlyZygoteLaunch() {
+  DCHECK(!g_utility_zygote);
+  g_utility_zygote = CreateZygote();
+}
+#endif  // defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
+
 bool UtilityProcessHostImpl::StartProcess() {
   if (started_)
     return true;