Revert of Use a token to initialise ChannelMojo and MojoApplication everywhere.

content/browser/mojo/mojo_application_host.cc

Index: content/browser/mojo/mojo_application_host.cc
diff --git a/content/browser/mojo/mojo_application_host.cc b/content/browser/mojo/mojo_application_host.cc
index 1e5f1f439187268754d3c73a499e84208df1dea4..6456a943a53e2847ee157ee554a788a0d459a54c 100644
--- a/content/browser/mojo/mojo_application_host.cc
+++ b/content/browser/mojo/mojo_application_host.cc
@@ -6,9 +6,12 @@
 
 #include <utility>
 
-#include "base/logging.h"
 #include "build/build_config.h"
+#include "content/common/mojo/mojo_messages.h"
+#include "content/public/browser/browser_thread.h"
+#include "ipc/ipc_sender.h"
 #include "mojo/edk/embedder/embedder.h"
+#include "mojo/edk/embedder/platform_channel_pair.h"
 
 namespace content {
 namespace {
@@ -38,22 +41,70 @@
 
 }  // namespace
 
-MojoApplicationHost::MojoApplicationHost()
-    : token_(mojo::edk::GenerateRandomToken()) {
+MojoApplicationHost::MojoApplicationHost() : did_activate_(false) {
 #if defined(OS_ANDROID)
   service_registry_android_ =
       ServiceRegistryAndroid::Create(&service_registry_);
 #endif
-
-  mojo::ScopedMessagePipeHandle pipe =
-      mojo::edk::CreateParentMessagePipe(token_);
-  DCHECK(pipe.is_valid());
-  application_setup_.reset(new ApplicationSetupImpl(
-      &service_registry_,
-      mojo::MakeRequest<mojom::ApplicationSetup>(std::move(pipe))));
 }
 
 MojoApplicationHost::~MojoApplicationHost() {
 }
 
+bool MojoApplicationHost::Init() {
+  DCHECK(!client_handle_.is_valid()) << "Already initialized!";
+
+  mojo::edk::PlatformChannelPair channel_pair;
+
+  scoped_refptr<base::TaskRunner> io_task_runner;
+  if (io_task_runner_override_) {
+    io_task_runner = io_task_runner_override_;
+  } else {
+    io_task_runner =
+        BrowserThread::UnsafeGetMessageLoopForThread(BrowserThread::IO)
+          ->task_runner();
+  }
+
+  // Forward this to the client once we know its process handle.
+  client_handle_ = channel_pair.PassClientHandle();
+  mojo::ScopedMessagePipeHandle pipe = channel_init_.Init(
+      channel_pair.PassServerHandle().release().handle, io_task_runner);
+  application_setup_.reset(new ApplicationSetupImpl(
+      &service_registry_,
+      mojo::MakeRequest<mojom::ApplicationSetup>(std::move(pipe))));
+  return true;
+}
+
+void MojoApplicationHost::Activate(IPC::Sender* sender,
+                                   base::ProcessHandle process_handle) {
+  DCHECK(!did_activate_);
+  DCHECK(client_handle_.is_valid());
+
+  base::PlatformFile client_file = client_handle_.release().handle;
+  did_activate_ = sender->Send(new MojoMsg_Activate(
+      IPC::GetPlatformFileForTransit(client_file, true)));
+}
+
+std::string MojoApplicationHost::InitWithToken() {
+  DCHECK(!client_handle_.is_valid()) << "Already initialized!";
+  DCHECK(!did_activate_);
+
+  std::string token = mojo::edk::GenerateRandomToken();
+  mojo::ScopedMessagePipeHandle pipe =
+      mojo::edk::CreateParentMessagePipe(token);
+  DCHECK(pipe.is_valid());
+  application_setup_.reset(new ApplicationSetupImpl(
+      &service_registry_,
+      mojo::MakeRequest<mojom::ApplicationSetup>(std::move(pipe))));
+
+  did_activate_ = true;
+  return token;
+}
+
+void MojoApplicationHost::OverrideIOTaskRunnerForTest(
+    scoped_refptr<base::TaskRunner> io_task_runner) {
+  io_task_runner_override_ = io_task_runner;
+}
+
+
 }  // namespace content