Add multiplexing of message pipes in the new EDK.

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index 4c2413e3d4a8a3efa4e1a53eadba43776fadcc44..d9058f705ba0ca3f0393a644a658c345e8989758 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -2479,8 +2479,6 @@ void RenderProcessHostImpl::OnProcessLaunched() {
   SendExternalMojoShellHandleToChild(GetHandle(), this);
 #endif
 
-#if defined(OS_WIN)
-  // TODO(jam): enable on POSIX
   if (base::CommandLine::ForCurrentProcess()->HasSwitch("use-new-edk") &&
       child_process_launcher_.get()) {
     base::ProcessHandle process_handle =
@@ -2496,7 +2494,6 @@ void RenderProcessHostImpl::OnProcessLaunched() {
 #endif
                                      process_handle, true)));
   }
-#endif
 
   // Allow Mojo to be setup before the renderer sees any Chrome IPC messages.
   // This way, Mojo can be safely used from the renderer in response to any