[mojo-edk] Add support for transferring mach ports.

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 e438033ed958ec373b3db13e029dbcb13cceaa3f..7459fbc8e1486fde09a0a9ae33374bbedabecd1d 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -623,6 +623,9 @@ RenderProcessHostImpl::RenderProcessHostImpl(
   IPC::AttachmentBrokerPrivileged::CreateBrokerIfNeeded();
 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 #endif  // USE_ATTACHMENT_BROKER
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+  mojo::edk::SetMachPortProviderIfNeeded(MachBroker::GetInstance());

[Ken Rockot(use gerrit already), 2016/03/09 08:34:31]

I'm confused about why this (and really the AttachmentBrokerPrivileged above) is
created here instead of somewhere a bit more generic. If this is a
process-global thing, why is RPHI responsible for ensuring it exists, and why
does every RPHI instance do it? Why not BrowserMainLoop or some other very-early
initialization?

[erikchen, 2016/03/09 19:13:16]

That would be cleaner.

Right now, we actually call this same logic in 3 different places (you'll have
to do the same for mojo::edk as well)
https://code.google.com/p/chromium/codesearch#search/&q=brokerprivileged::Cre...

The idea was that we should attempt to lazy initialize, and only perform this
setup when we need it (which is when the browser tries to make a child process).

[Anand Mistry (off Chromium), 2016/03/11 07:44:17]

I agree, but think it's outside the scope of this CL.
I've added it to the one other place. The other (ChildProcessHostImpl) doesn't
actually create the broker on mac. Maybe that's a bug?

+#endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 }
 
 // static