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

content/public/browser/zygote_handle_linux.h

Index: content/public/browser/zygote_handle_linux.h
diff --git a/content/public/browser/zygote_handle_linux.h b/content/public/browser/zygote_handle_linux.h
index b644c514b60775ae4c1c03cb73b3e15a53e5e315..93da60f8d763bded1452fb551392904b988de173 100644
--- a/content/public/browser/zygote_handle_linux.h
+++ b/content/public/browser/zygote_handle_linux.h
@@ -16,6 +16,11 @@ namespace content {
 // ZygoteHandle used to communicate with it.
 CONTENT_EXPORT ZygoteHandle CreateZygote();
 
+// Returns a handle to a global generic zygote object. This function allows the
+// browser to launch and use a single zygote process until the performance
+// issues around launching multiple zygotes are resolved.
+CONTENT_EXPORT ZygoteHandle GetGenericZygote();
+
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_ZYGOTE_HANDLE_LINUX_H_