Move the Linux zygote stuff into its own per-process directory.

content/browser/zygote_host_impl_linux.h

Index: content/browser/zygote_host_impl_linux.h
diff --git a/content/browser/zygote_host_impl_linux.h b/content/browser/zygote_host_impl_linux.h
index ad8dfac26223f4712482253f76729105d50baaa8..e091bab325468cb58f01247056728b8eeff8137a 100644
--- a/content/browser/zygote_host_impl_linux.h
+++ b/content/browser/zygote_host_impl_linux.h
@@ -17,8 +17,6 @@
 template<typename Type>
 struct DefaultSingletonTraits;
 
-static const char kZygoteMagic[] = "ZYGOTE_OK";
-
 class CONTENT_EXPORT ZygoteHostImpl : public content::ZygoteHost {
  public:
   // Returns the singleton instance.
@@ -40,15 +38,6 @@ class CONTENT_EXPORT ZygoteHostImpl : public content::ZygoteHost {
   base::TerminationStatus GetTerminationStatus(base::ProcessHandle handle,
                                                int* exit_code);
 
-  // These are the command codes used on the wire between the browser and the
-  // zygote.
-  enum {
-    kCmdFork = 0,                  // Fork off a new renderer.
-    kCmdReap = 1,                  // Reap a renderer child.
-    kCmdGetTerminationStatus = 2,  // Check what happend to a child process.
-    kCmdGetSandboxStatus = 3,      // Read a bitmask of kSandbox*
-  };
-
   // ZygoteHost implementation:
   virtual pid_t GetPid() const OVERRIDE;
   virtual pid_t GetSandboxHelperPid() const OVERRIDE;