Revert of Move content's shell connections to the IO thread

services/shell/public/cpp/lib/interface_provider.cc

Index: services/shell/public/cpp/lib/interface_provider.cc
diff --git a/services/shell/public/cpp/lib/interface_provider.cc b/services/shell/public/cpp/lib/interface_provider.cc
index 0934ee15ce2803570448310547e73216da6a4a18..209d356ac476bb6a79d8cfc51f389500c8b297b7 100644
--- a/services/shell/public/cpp/lib/interface_provider.cc
+++ b/services/shell/public/cpp/lib/interface_provider.cc
@@ -4,30 +4,17 @@
 
 #include "services/shell/public/cpp/interface_provider.h"
 
-#include "base/macros.h"
-#include "mojo/public/cpp/bindings/strong_binding.h"
-
 namespace shell {
 
 InterfaceProvider::InterfaceProvider() : weak_factory_(this) {
   pending_request_ = GetProxy(&interface_provider_);
 }
-
 InterfaceProvider::~InterfaceProvider() {}
 
 void InterfaceProvider::Bind(mojom::InterfaceProviderPtr interface_provider) {
   DCHECK(pending_request_.is_pending());
-  DCHECK(forward_callback_.is_null());
   mojo::FuseInterface(std::move(pending_request_),
                       interface_provider.PassInterface());
-}
-
-void InterfaceProvider::Forward(const ForwardCallback& callback) {
-  DCHECK(pending_request_.is_pending());
-  DCHECK(forward_callback_.is_null());
-  interface_provider_.reset();
-  pending_request_.PassMessagePipe().reset();
-  forward_callback_ = callback;
 }
 
 void InterfaceProvider::SetConnectionLostClosure(
@@ -48,14 +35,7 @@
     it->second.Run(std::move(request_handle));
     return;
   }
-
-  if (!forward_callback_.is_null()) {
-    DCHECK(!interface_provider_.is_bound());
-    forward_callback_.Run(name, std::move(request_handle));
-  } else {
-    DCHECK(interface_provider_.is_bound());
-    interface_provider_->GetInterface(name, std::move(request_handle));
-  }
+  interface_provider_->GetInterface(name, std::move(request_handle));
 }
 
 void InterfaceProvider::ClearBinders() {