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

content/browser/browser_child_process_host_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/browser_child_process_host_impl.h"
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/dump_without_crashing.h"
@@ skipping 123 matching lines @@
   // child process. This ensures that when a test is being run in one of the
   // single process modes, the global attachment broker is the privileged
   // attachment broker, rather than an unprivileged attachment broker.
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   IPC::AttachmentBrokerPrivileged::CreateBrokerIfNeeded(
       MachBroker::GetInstance());
 #else
   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());

[jam, 2016/03/15 16:27:42]

it doesn't make sense that this code is run each time a child process is
created, given that it's a single time initialization. i realize this just
copies what the previous block does, but i think that's wrong. they should both
be done once in content's browser initialization code, i.e. in
BrowserMainLoop::PostMainMessageLoopStart()

[Anand Mistry (off Chromium), 2016/03/15 20:26:10]

I agree, but I think it should be done to both Mojo and IPC, not just one (it
would be confusing to have IPC here and Mojo elsewhere). I would like to keep
this here for this change, and do a follow up that moves both to
BrowserMainLoop.

[jam, 2016/03/15 23:13:09]

yep I meant do both. can they just be moved in this cl? that should be a small
change

[Anand Mistry (off Chromium), 2016/03/15 23:30:56]

It is small, but this change is already big and complicated. I'd rather leave it
to a separate cl.

+#endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 
   child_process_host_.reset(ChildProcessHost::Create(this));
   AddFilter(new TraceMessageFilter(data_.id));
   AddFilter(new ProfilerMessageFilter(process_type));
   AddFilter(new HistogramMessageFilter);
   AddFilter(new MemoryMessageFilter(this, process_type));
 
   g_child_process_list.Get().push_back(this);
   GetContentClient()->browser()->BrowserChildProcessHostCreated(this);
 
@@ skipping 286 matching lines @@
 
 #if defined(OS_WIN)
 
 void BrowserChildProcessHostImpl::OnObjectSignaled(HANDLE object) {
   OnChildDisconnected();
 }
 
 #endif
 
 }  // namespace content