Revert of [mojo-edk] Simplify multiprocess pipe bootstrap

mojo/shell/runner/host/child_process.cc

Index: mojo/shell/runner/host/child_process.cc
diff --git a/mojo/shell/runner/host/child_process.cc b/mojo/shell/runner/host/child_process.cc
index 75230f096baa7471c16d78f129fb3ed3068833eb..0208b8408c0ba77a5eccf3081020840afb388109 100644
--- a/mojo/shell/runner/host/child_process.cc
+++ b/mojo/shell/runner/host/child_process.cc
@@ -51,6 +51,10 @@
 
 namespace {
 
+void DidCreateChannel(embedder::ChannelInfo* channel_info) {
+  DVLOG(2) << "ChildControllerImpl::DidCreateChannel()";
+}
+
 // Blocker ---------------------------------------------------------------------
 
 // Blocks a thread until another thread unblocks it, at which point it unblocks
@@ -296,14 +300,34 @@
 }
 #endif
 
-ScopedMessagePipeHandle InitializeHostMessagePipe(
-    edk::ScopedPlatformHandle platform_channel,
-    scoped_refptr<base::TaskRunner> io_task_runner) {
-  edk::SetParentPipeHandle(std::move(platform_channel));
-  std::string primordial_pipe_token =
-      base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
-          switches::kPrimordialPipeToken);
-  return edk::CreateChildMessagePipe(primordial_pipe_token);
+void InitializeHostMessagePipe(
+    embedder::ScopedPlatformHandle platform_channel,
+    scoped_refptr<base::TaskRunner> io_task_runner,
+    const base::Callback<void(ScopedMessagePipeHandle)>& callback) {
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch("use-new-edk")) {
+    embedder::SetParentPipeHandle(std::move(platform_channel));
+    std::string primordial_pipe_token =
+        base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
+            switches::kPrimordialPipeToken);
+    edk::CreateChildMessagePipe(primordial_pipe_token, callback);
+  } else {
+    ScopedMessagePipeHandle host_message_pipe;
+    host_message_pipe =
+        embedder::CreateChannel(std::move(platform_channel),
+                                base::Bind(&DidCreateChannel), io_task_runner);
+    callback.Run(std::move(host_message_pipe));
+  }
+}
+
+void OnHostMessagePipeCreated(AppContext* app_context,
+                              base::NativeLibrary app_library,
+                              const Blocker::Unblocker& unblocker,
+                              ScopedMessagePipeHandle pipe) {
+  app_context->controller_runner()->PostTask(
+      FROM_HERE,
+      base::Bind(&ChildControllerImpl::Init, base::Unretained(app_context),
+                 base::Unretained(app_library), base::Passed(&pipe),
+                 unblocker));
 }
 
 }  // namespace
@@ -336,8 +360,8 @@
     sandbox = InitializeSandbox();
 #endif
 
-  edk::ScopedPlatformHandle platform_channel =
-      edk::PlatformChannelPair::PassClientHandleFromParentProcess(
+  embedder::ScopedPlatformHandle platform_channel =
+      embedder::PlatformChannelPair::PassClientHandleFromParentProcess(
           command_line);
   CHECK(platform_channel.is_valid());
 
@@ -348,12 +372,13 @@
   app_context.Init();
   app_context.StartControllerThread();
 
-  ScopedMessagePipeHandle host_pipe = InitializeHostMessagePipe(
-      std::move(platform_channel), app_context.io_runner());
   app_context.controller_runner()->PostTask(
       FROM_HERE,
-      base::Bind(&ChildControllerImpl::Init, &app_context, app_library,
-                 base::Passed(&host_pipe), blocker.GetUnblocker()));
+      base::Bind(
+          &InitializeHostMessagePipe, base::Passed(&platform_channel),
+          make_scoped_refptr(app_context.io_runner()),
+          base::Bind(&OnHostMessagePipeCreated, base::Unretained(&app_context),
+                     base::Unretained(app_library), blocker.GetUnblocker())));
 
   // This will block, then run whatever the controller wants.
   blocker.Block();