Have each SandboxedProcessLauncherDelegate maintain a zygote.

content/browser/zygote_host/zygote_handle_linux.cc

Index: content/browser/zygote_host/zygote_handle_linux.cc
diff --git a/content/browser/zygote_host/zygote_handle_linux.cc b/content/browser/zygote_host/zygote_handle_linux.cc
new file mode 100644
index 0000000000000000000000000000000000000000..89adc49385b4364803f4cd14fc64a4e7fbfa25d6
--- /dev/null
+++ b/content/browser/zygote_host/zygote_handle_linux.cc
@@ -0,0 +1,17 @@
+// Copyright 2016 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/public/browser/zygote_handle_linux.h"
+
+#include "content/browser/zygote_host/zygote_communication_linux.h"
+
+namespace content {
+
+ZygoteHandle CreateZygote() {
+  ZygoteHandle zygote = new ZygoteCommunication();
+  zygote->Init();
+  return zygote;
+}
+
+}  // namespace content