Use a single, generic, global zygote to temporarily resolve perf regressions.

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 766a71390626c82162264baea8000721580708f6..377335b0b9796815484efabbfed7a1316dbc4cef 100644
--- a/content/browser/ppapi_plugin_process_host.cc
+++ b/content/browser/ppapi_plugin_process_host.cc
@@ -116,7 +116,8 @@ class PpapiPluginSandboxedProcessLauncherDelegate
         .GetSwitchValueNative(switches::kPpapiPluginLauncher);
     if (is_broker_ || !plugin_launcher.empty())
       return nullptr;
-    return &g_ppapi_zygote;
+    static ZygoteHandle zygote = GetGenericZygote();
+    return &zygote;
   }
 #endif  // !defined(OS_MACOSX) && !defined(OS_ANDROID)