Use ChannelMojo for the utility process.

BUG=604282,597124

Review-Url: https://codereview.chromium.org/1959313002
Cr-Commit-Position: refs/heads/master@{#398221}

content/browser/utility_process_host_impl.cc

@@ -256,8 +256,9 @@ bool UtilityProcessHostImpl::StartProcess() {
                                                  child_token_));
   process_->SetName(name_);
 
-  std::string channel_id = process_->GetHost()->CreateChannel();
-  if (channel_id.empty()) {
+  std::string mojo_channel_token =
+      process_->GetHost()->CreateChannelMojo(child_token_);
+  if (mojo_channel_token.empty()) {
     NotifyAndDelete(LAUNCH_RESULT_FAILURE);
     return false;
   }
@@ -268,9 +269,9 @@ bool UtilityProcessHostImpl::StartProcess() {
     // support single process mode this way.
     in_process_thread_.reset(
         g_utility_main_thread_factory(InProcessChildThreadParams(
-            channel_id, BrowserThread::UnsafeGetMessageLoopForThread(
+            std::string(), BrowserThread::UnsafeGetMessageLoopForThread(
                             BrowserThread::IO)->task_runner(),
-            std::string(), mojo_application_host_->GetToken())));
+            mojo_channel_token, mojo_application_host_->GetToken())));
     in_process_thread_->Start();
   } else {
     const base::CommandLine& browser_command_line =
@@ -307,7 +308,8 @@ bool UtilityProcessHostImpl::StartProcess() {
 
     cmd_line->AppendSwitchASCII(switches::kProcessType,
                                 switches::kUtilityProcess);
-    cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id);
+    cmd_line->AppendSwitchASCII(switches::kMojoChannelToken,
+                                mojo_channel_token);
     std::string locale = GetContentClient()->browser()->GetApplicationLocale();
     cmd_line->AppendSwitchASCII(switches::kLang, locale);
 

content/child/child_thread_impl.cc

@@ -262,7 +262,8 @@ ChildThread* ChildThread::Get() {
 ChildThreadImpl::Options::Options()
     : channel_name(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
           switches::kProcessChannelID)),
-      use_mojo_channel(false) {
+      use_mojo_channel(base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kMojoChannelToken)) {
 }
 
 ChildThreadImpl::Options::Options(const Options& other) = default;

content/common/child_process_host_impl.cc

@@ -31,6 +31,8 @@
 #include "ipc/ipc_channel.h"
 #include "ipc/ipc_logging.h"
 #include "ipc/message_filter.h"
+#include "ipc/mojo/ipc_channel_mojo.h"
+#include "mojo/edk/embedder/embedder.h"
 
 #if defined(OS_LINUX)
 #include "base/linux_util.h"
@@ -130,9 +132,31 @@ void ChildProcessHostImpl::ForceShutdown() {
   Send(new ChildProcessMsg_Shutdown());
 }
 
+std::string ChildProcessHostImpl::CreateChannelMojo(
+    const std::string& child_token) {
+  DCHECK(channel_id_.empty());
+  channel_id_ = mojo::edk::GenerateRandomToken();
+  mojo::ScopedMessagePipeHandle host_handle =
+      mojo::edk::CreateParentMessagePipe(channel_id_, child_token);
+  channel_ = IPC::ChannelMojo::Create(std::move(host_handle),
+                                      IPC::Channel::MODE_SERVER, this);
+  if (!channel_ || !InitChannel())
+    return std::string();
+
+  return channel_id_;
+}
+
 std::string ChildProcessHostImpl::CreateChannel() {
+  DCHECK(channel_id_.empty());
   channel_id_ = IPC::Channel::GenerateVerifiedChannelID(std::string());
   channel_ = IPC::Channel::CreateServer(channel_id_, this);
+  if (!channel_ || !InitChannel())
+    return std::string();
+
+  return channel_id_;
+}
+
+bool ChildProcessHostImpl::InitChannel() {
 #if USE_ATTACHMENT_BROKER
   IPC::AttachmentBroker::GetGlobal()->RegisterCommunicationChannel(
       channel_.get(), base::MessageLoopForIO::current()->task_runner());
@@ -142,7 +166,7 @@ std::string ChildProcessHostImpl::CreateChannel() {
     IPC::AttachmentBroker::GetGlobal()->DeregisterCommunicationChannel(
         channel_.get());
 #endif
-    return std::string();
+    return false;
   }
 
   for (size_t i = 0; i < filters_.size(); ++i)
@@ -156,7 +180,7 @@ std::string ChildProcessHostImpl::CreateChannel() {
 
   opening_channel_ = true;
 
-  return channel_id_;
+  return true;
 }
 
 bool ChildProcessHostImpl::IsChannelOpening() {

content/common/child_process_host_impl.h

@@ -79,6 +79,7 @@ class CONTENT_EXPORT ChildProcessHostImpl : public ChildProcessHost,
   bool Send(IPC::Message* message) override;
   void ForceShutdown() override;
   std::string CreateChannel() override;
+  std::string CreateChannelMojo(const std::string& child_token) override;
   bool IsChannelOpening() override;
   void AddFilter(IPC::MessageFilter* filter) override;
 #if defined(OS_POSIX)
@@ -109,6 +110,10 @@ class CONTENT_EXPORT ChildProcessHostImpl : public ChildProcessHost,
   void OnDeletedGpuMemoryBuffer(gfx::GpuMemoryBufferId id,
                                 const gpu::SyncToken& sync_token);
 
+  // Initializes the IPC channel and returns true on success. |channel_| must be
+  // non-null.
+  bool InitChannel();
+
   ChildProcessHostDelegate* delegate_;
   base::Process peer_process_;
   bool opening_channel_;  // True while we're waiting the channel to be opened.

content/public/common/child_process_host.h

@@ -81,6 +81,10 @@ class CONTENT_EXPORT ChildProcessHost : public IPC::Sender {
   // empty string otherwise
   virtual std::string CreateChannel() = 0;
 
+  // Creates the IPC channel on top of Mojo. Returns the Mojo channel token if
+  // succeeded, or an empty string on failure.
+  virtual std::string CreateChannelMojo(const std::string& child_token) = 0;
+
   // Returns true iff the IPC channel is currently being opened;
   virtual bool IsChannelOpening() = 0;
 

content/utility/utility_thread_impl.cc

@@ -46,6 +46,7 @@ UtilityThreadImpl::UtilityThreadImpl()
 UtilityThreadImpl::UtilityThreadImpl(const InProcessChildThreadParams& params)
     : ChildThreadImpl(ChildThreadImpl::Options::Builder()
                           .InBrowserProcess(params)
+                          .UseMojoChannel(true)
                           .Build()) {
   Init();
 }