Bootstrap Mojo IPC independent of Chrome IPC

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 0d62e29ced2559b145dca73b2de51eabfd3b27aa..463377cd19250bc3bd6759d10476ce4718a1bb2e 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -628,7 +628,7 @@ RenderProcessHostImpl::RenderProcessHostImpl(
 #endif  // USE_ATTACHMENT_BROKER
 
 #if defined(MOJO_SHELL_CLIENT)
-  RegisterChildWithExternalShell(id_, this);
+  shell_pipe_token_ = RegisterChildWithExternalShell(id_, this);
 #endif
 }
 
@@ -1623,6 +1623,10 @@ void RenderProcessHostImpl::PropagateBrowserCommandLineToRenderer(
 #if defined(MOJO_SHELL_CLIENT)
   if (IsRunningInMojoShell())
     renderer_cmd->AppendSwitch(switches::kEnableMojoShellConnection);
+  if (!shell_pipe_token_.empty()) {
+    renderer_cmd->AppendSwitchASCII(switches::kMojoPrimordialPipeToken,
+                                    shell_pipe_token_);

[jam, 2016/02/13 04:15:13]

You'll want to do the same thing in BrowserChildProcessHostImpl so that this
pipe is also setup for non-renderer processes

[Ken Rockot(use gerrit already), 2016/02/13 04:35:09]

Yeah, I'm intentionally keeping this on render processes only for this CL. My
plan is to expand this to all child processes soon.

+  }
 #endif
 }
 
@@ -2566,21 +2570,6 @@ void RenderProcessHostImpl::OnProcessLaunched() {
                                          Source<RenderProcessHost>(this),
                                          NotificationService::NoDetails());
 
-  if (child_process_launcher_.get()) {
-    base::ProcessHandle process_handle =
-        child_process_launcher_->GetProcess().Handle();
-    mojo::edk::ScopedPlatformHandle client_pipe =
-        mojo::edk::ChildProcessLaunched(process_handle);
-    Send(new ChildProcessMsg_SetMojoParentPipeHandle(
-        IPC::GetFileHandleForProcess(client_pipe.release().handle,
-                                     process_handle, true)));
-  }
-
-#if defined(MOJO_SHELL_CLIENT)
-  // Send the mojo shell handle to the renderer.
-  SendExternalMojoShellHandleToChild(GetHandle(), this);
-#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
   // Chrome IPC message.