[Chromoting] Reimplemented the worker process launcher to take into account the encountered issues:

remoting/host/win/wts_console_session_process_driver.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// This file implements the Windows service controlling Me2Me host processes
+// running within user sessions.
+
+#include "remoting/host/win/wts_console_session_process_driver.h"
+
+#include <sddl.h>
+#include <limits>
+
+#include "base/base_switches.h"
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/file_path.h"
+#include "base/logging.h"
+#include "base/single_thread_task_runner.h"
+#include "base/path_service.h"
+#include "ipc/ipc_message.h"
+#include "remoting/host/win/worker_process_launcher.h"
+#include "remoting/host/win/wts_console_monitor.h"
+#include "remoting/host/win/wts_session_process_delegate.h"
+
+namespace {
+
+const FilePath::CharType kMe2meHostBinaryName[] =
+    FILE_PATH_LITERAL("remoting_host.exe");
+
+// The security descriptor of the daemon IPC endpoint. It gives full access
+// to LocalSystem and denies access by anyone else.
+const char kDaemonIpcSecurityDescriptor[] = "O:SYG:SYD:(A;;GA;;;SY)";
+
+} // namespace
+
+namespace remoting {
+
+WtsConsoleSessionProcessDriver::WtsConsoleSessionProcessDriver(
+    const base::Closure& stopped_callback,
+    WtsConsoleMonitor* monitor,
+    scoped_refptr<base::SingleThreadTaskRunner> main_message_loop,
+    scoped_refptr<base::SingleThreadTaskRunner> io_task_runner)
+    : Stoppable(main_message_loop, stopped_callback),
+      main_task_runner_(main_message_loop),
+      io_task_runner_(io_task_runner),
+      monitor_(monitor) {
+  monitor_->AddWtsConsoleObserver(this);
+}
+
+WtsConsoleSessionProcessDriver::~WtsConsoleSessionProcessDriver() {
+  // Make sure that the object is completely stopped. The same check exists
+  // in Stoppable::~Stoppable() but this one helps us to fail early and
+  // predictably.
+  CHECK_EQ(stoppable_state(), Stoppable::kStopped);
+
+  monitor_->RemoveWtsConsoleObserver(this);
+
+  CHECK(launcher_.get() == NULL);
+}
+
+void WtsConsoleSessionProcessDriver::OnChannelConnected() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+}
+
+bool WtsConsoleSessionProcessDriver::OnMessageReceived(
+    const IPC::Message& message) {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+
+  return false;
+}
+
+void WtsConsoleSessionProcessDriver::OnPermanentError() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+
+  Stop();
+}
+
+void WtsConsoleSessionProcessDriver::OnSessionAttached(uint32 session_id) {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+
+  if (stoppable_state() != Stoppable::kRunning) {
+    return;
+  }
+
+  DCHECK(launcher_.get() == NULL);
+
+  // Construct the host binary name.
+  FilePath dir_path;
+  if (!PathService::Get(base::DIR_EXE, &dir_path)) {
+    LOG(ERROR) << "Failed to get the executable file name.";
+    Stop();
+    return;
+  }
+  FilePath host_binary = dir_path.Append(kMe2meHostBinaryName);
+
+  // Create the delegate knowing how to launch a process in a session.
+  scoped_ptr<WtsSessionProcessDelegate> delegate(
+      new WtsSessionProcessDelegate(main_task_runner_,
+                                    io_task_runner_,
+                                    host_binary,
+                                    session_id,
+                                    true));
+
+  // Create a per-session launcher that will start the host process.
+  launcher_ = new WorkerProcessLauncher(main_task_runner_,
+                                        io_task_runner_,
+                                        delegate.Pass(),
+                                        this,
+                                        kDaemonIpcSecurityDescriptor);
+}
+
+void WtsConsoleSessionProcessDriver::OnSessionDetached() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+  DCHECK(launcher_.get() != NULL);
+
+  launcher_->Stop();
+  launcher_ = NULL;
+}
+
+void WtsConsoleSessionProcessDriver::DoStop() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+
+  if (launcher_.get() != NULL) {
+    launcher_->Stop();
+    launcher_ = NULL;
+  }
+
+  CompleteStopping();
+}
+
+} // namespace remoting