Convert UtilityProcess to use MojoChild/ShellConnection for the shell handshake.

content/browser/utility_process_host_impl.cc

Index: content/browser/utility_process_host_impl.cc
diff --git a/content/browser/utility_process_host_impl.cc b/content/browser/utility_process_host_impl.cc
index 89e9c9f9e75640d18e40d4e80a36da12e8ad8123..4debf70b740f42076725968aad15831228f46120 100644
--- a/content/browser/utility_process_host_impl.cc
+++ b/content/browser/utility_process_host_impl.cc
@@ -17,12 +17,15 @@
 #include "base/process/process_handle.h"
 #include "base/run_loop.h"
 #include "base/sequenced_task_runner.h"
+#include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/synchronization/lock.h"
 #include "base/synchronization/waitable_event.h"
 #include "build/build_config.h"
 #include "content/browser/browser_child_process_host_impl.h"
-#include "content/browser/mojo/mojo_application_host.h"
+#include "content/browser/mojo/constants.h"
+#include "content/browser/mojo/mojo_child_connection.h"
+#include "content/browser/mojo/mojo_shell_context.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/common/child_process_host_impl.h"
 #include "content/common/in_process_child_thread_params.h"
@@ -32,11 +35,13 @@
 #include "content/public/browser/utility_process_host_client.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/mojo_channel_switches.h"
+#include "content/public/common/mojo_shell_connection.h"
 #include "content/public/common/process_type.h"
 #include "content/public/common/sandbox_type.h"
 #include "content/public/common/sandboxed_process_launcher_delegate.h"
 #include "ipc/ipc_switches.h"
 #include "mojo/edk/embedder/embedder.h"
+#include "services/shell/public/cpp/connection.h"
 #include "services/shell/public/cpp/interface_provider.h"
 #include "services/shell/public/cpp/interface_registry.h"
 #include "ui/base/ui_base_switches.h"
@@ -162,8 +167,14 @@ UtilityProcessHostImpl::UtilityProcessHostImpl(
       started_(false),
       name_(base::ASCIIToUTF16("utility process")),
       child_token_(mojo::edk::GenerateRandomToken()),
-      mojo_application_host_(new MojoApplicationHost(child_token_)),
       weak_ptr_factory_(this) {
+  process_.reset(new BrowserChildProcessHostImpl(PROCESS_TYPE_UTILITY, this,
+                                                 child_token_));
+  mojo_child_connection_.reset(new MojoChildConnection(
+      kUtilityMojoApplicationName,
+      base::StringPrintf("%d_0", process_->GetData().id),
+      child_token_,
+      MojoShellContext::GetConnectorForIOThread()));
 }
 
 UtilityProcessHostImpl::~UtilityProcessHostImpl() {
@@ -228,13 +239,11 @@ bool UtilityProcessHostImpl::Start() {
 }
 
 shell::InterfaceRegistry* UtilityProcessHostImpl::GetInterfaceRegistry() {
-  DCHECK(mojo_application_host_);
-  return mojo_application_host_->interface_registry();
+  return mojo_child_connection_->connection()->GetInterfaceRegistry();
 }
 
 shell::InterfaceProvider* UtilityProcessHostImpl::GetRemoteInterfaces() {
-  DCHECK(mojo_application_host_);
-  return mojo_application_host_->remote_interfaces();
+  return mojo_child_connection_->connection()->GetRemoteInterfaces();
 }
 
 void UtilityProcessHostImpl::SetName(const base::string16& name) {
@@ -257,10 +266,6 @@ bool UtilityProcessHostImpl::StartProcess() {
   if (is_batch_mode_)
     return true;
 
-  // Name must be set or metrics_service will crash in any test which
-  // launches a UtilityProcessHost.
-  process_.reset(new BrowserChildProcessHostImpl(PROCESS_TYPE_UTILITY, this,
-                                                 child_token_));
   process_->SetName(name_);
 
   std::string mojo_channel_token =
@@ -278,7 +283,7 @@ bool UtilityProcessHostImpl::StartProcess() {
         g_utility_main_thread_factory(InProcessChildThreadParams(
             std::string(), BrowserThread::UnsafeGetMessageLoopForThread(
                             BrowserThread::IO)->task_runner(),
-            mojo_channel_token, mojo_application_host_->GetToken())));
+            mojo_channel_token, mojo_child_connection_->shell_client_token())));
     in_process_thread_->Start();
   } else {
     const base::CommandLine& browser_command_line =
@@ -357,7 +362,7 @@ bool UtilityProcessHostImpl::StartProcess() {
 #endif
 
     cmd_line->AppendSwitchASCII(switches::kMojoApplicationChannelToken,
-                                mojo_application_host_->GetToken());
+                                mojo_child_connection_->shell_client_token());
 
     process_->Launch(
         new UtilitySandboxedProcessLauncherDelegate(exposed_dir_,