borealis: Add a monitor to assist shutting borealis down with a delay

This monitor will be sent requests to shutdown borealis with or without
a delay, and it will act on those requests at the appropriate times.

Bug: b/172006764
Change-Id: I81fb0cb73cfb1c868a6ebc8000cfa044a1569a21
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2569323
Commit-Queue: Nic Hollingum <hollingum@google.com>
Reviewed-by: Daniel Ng <danielng@google.com>
Cr-Commit-Position: refs/heads/master@{#833555}

chrome/browser/chromeos/BUILD.gn

@@ -891,6 +891,8 @@ source_set("chromeos") {
     "borealis/borealis_service_factory.h",
     "borealis/borealis_service_impl.cc",
     "borealis/borealis_service_impl.h",
+    "borealis/borealis_shutdown_monitor.cc",
+    "borealis/borealis_shutdown_monitor.h",
     "borealis/borealis_task.cc",
     "borealis/borealis_task.h",
     "borealis/borealis_util.cc",
@@ -3387,6 +3389,7 @@ source_set("unit_tests") {
     "borealis/borealis_features_unittest.cc",
     "borealis/borealis_installer_unittest.cc",
     "borealis/borealis_launch_watcher_unittest.cc",
+    "borealis/borealis_shutdown_monitor_unittest.cc",
     "borealis/borealis_task_unittest.cc",
     "borealis/borealis_window_manager_unittest.cc",
     "borealis/infra/described_unittest.cc",

chrome/browser/chromeos/borealis/borealis_shutdown_monitor.cc

+// Copyright 2020 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.
+
+#include "chrome/browser/chromeos/borealis/borealis_shutdown_monitor.h"
+
+#include "base/threading/thread_task_runner_handle.h"
+#include "chrome/browser/chromeos/borealis/borealis_context_manager.h"
+#include "chrome/browser/chromeos/borealis/borealis_service.h"
+
+namespace {
+
+// The default time period used when initiating delayed shutdowns.
+constexpr base::TimeDelta kDefaultDelay = base::TimeDelta::FromSeconds(60);
+
+}  // namespace
+
+namespace borealis {
+
+BorealisShutdownMonitor::BorealisShutdownMonitor(Profile* profile)
+    : profile_(profile), delay_(kDefaultDelay) {}
+
+BorealisShutdownMonitor::~BorealisShutdownMonitor() = default;
+
+void BorealisShutdownMonitor::ShutdownWithDelay() {
+  // Reset() cancels the previous request if it was already there. Also,
+  // Unretained() is safe because the callback is cancelled when
+  // |in_progress_request_| is destroyed.
+  in_progress_request_.Reset(base::BindOnce(
+      &BorealisShutdownMonitor::ShutdownNow, base::Unretained(this)));
+  base::SequencedTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, in_progress_request_.callback(), delay_);
+}
+
+void BorealisShutdownMonitor::ShutdownNow() {
+  BorealisService::GetForProfile(profile_)->ContextManager().ShutDownBorealis();
+}
+
+void BorealisShutdownMonitor::CancelDelayedShutdown() {
+  in_progress_request_.Cancel();
+}
+
+void BorealisShutdownMonitor::SetShutdownDelayForTesting(
+    base::TimeDelta delay) {
+  delay_ = delay;
+}
+
+}  // namespace borealis

chrome/browser/chromeos/borealis/borealis_shutdown_monitor.h

+// Copyright 2020 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_BOREALIS_BOREALIS_SHUTDOWN_MONITOR_H_
+#define CHROME_BROWSER_CHROMEOS_BOREALIS_BOREALIS_SHUTDOWN_MONITOR_H_
+
+#include "base/cancelable_callback.h"
+#include "base/time/time.h"
+
+class Profile;
+
+namespace borealis {
+
+// Manages the automatic shutdown of borealis either immediately, or via a timed
+// delay.
+class BorealisShutdownMonitor {
+ public:
+  explicit BorealisShutdownMonitor(Profile* profile);
+  ~BorealisShutdownMonitor();
+
+  // Initiate a delayed shutdown, which will trigger the real shutdown after a
+  // fixed time period, unless the shutdown is aborted in the interim. If a
+  // delayed shutdown is in progress, this will reset the delay.
+  void ShutdownWithDelay();
+
+  // Initiate a shutdown immediately, without the delay.
+  void ShutdownNow();
+
+  // Cancels any in-progress delayed shutdowns.
+  void CancelDelayedShutdown();
+
+  // Overrides the default delay of the shutdown.
+  void SetShutdownDelayForTesting(base::TimeDelta delay);
+
+ private:
+  // The profile which we will shutdown borealis for.
+  Profile* profile_;
+
+  // The length of time we wait before issuing a shutdown after a delayed
+  // shutdown is requested.
+  base::TimeDelta delay_;
+
+  // The currently in-flight request to shutdown borealis. This will be in the
+  // default state unless a request is actually underway.
+  base::CancelableOnceClosure in_progress_request_;
+};
+
+}  // namespace borealis
+
+#endif  // CHROME_BROWSER_CHROMEOS_BOREALIS_BOREALIS_SHUTDOWN_MONITOR_H_

chrome/browser/chromeos/borealis/borealis_shutdown_monitor_unittest.cc

+// Copyright 2020 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.
+
+#include "chrome/browser/chromeos/borealis/borealis_shutdown_monitor.h"
+
+#include <memory>
+
+#include "chrome/browser/chromeos/borealis/borealis_context_manager.h"
+#include "chrome/browser/chromeos/borealis/borealis_features.h"
+#include "chrome/browser/chromeos/borealis/borealis_service_fake.h"
+#include "chrome/test/base/testing_profile.h"
+#include "content/public/test/browser_task_environment.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace borealis {
+namespace {
+
+class BorealisContextManagerMock : public BorealisContextManager {
+ public:
+  MOCK_METHOD(void,
+              StartBorealis,
+              (BorealisContextManager::ResultCallback),
+              ());
+  MOCK_METHOD(void, ShutDownBorealis, (), ());
+};
+
+class BorealisShutdownMonitorTest : public testing::Test {
+ protected:
+  BorealisShutdownMonitorTest()
+      : service_fake_(BorealisServiceFake::UseFakeForTesting(&profile_)),
+        features_(&profile_) {
+    service_fake_->SetFeaturesForTesting(&features_);
+    service_fake_->SetContextManagerForTesting(&context_manager_mock_);
+  }
+
+  Profile* profile() { return &profile_; }
+
+  content::BrowserTaskEnvironment task_environment_;
+  TestingProfile profile_;
+  BorealisServiceFake* service_fake_;
+  BorealisFeatures features_;
+  testing::StrictMock<BorealisContextManagerMock> context_manager_mock_;
+};
+
+TEST_F(BorealisShutdownMonitorTest, CanShutdownImmediately) {
+  BorealisShutdownMonitor monitor(profile());
+
+  EXPECT_CALL(context_manager_mock_, ShutDownBorealis());
+  monitor.ShutdownNow();
+}
+
+TEST_F(BorealisShutdownMonitorTest, CanShutdownWithDelay) {
+  BorealisShutdownMonitor monitor(profile());
+
+  monitor.SetShutdownDelayForTesting(base::TimeDelta::FromSeconds(0));
+  monitor.ShutdownWithDelay();
+
+  EXPECT_CALL(context_manager_mock_, ShutDownBorealis());
+  task_environment_.RunUntilIdle();
+}
+
+TEST_F(BorealisShutdownMonitorTest, CancelDelayedShutdownPreventsIt) {
+  BorealisShutdownMonitor monitor(profile());
+
+  EXPECT_CALL(context_manager_mock_, ShutDownBorealis()).Times(0);
+
+  monitor.SetShutdownDelayForTesting(base::TimeDelta::FromSeconds(0));
+  monitor.ShutdownWithDelay();
+
+  monitor.CancelDelayedShutdown();
+  task_environment_.RunUntilIdle();
+}
+
+TEST_F(BorealisShutdownMonitorTest, LaterShutdownOverridesEarlier) {
+  BorealisShutdownMonitor monitor(profile());
+
+  EXPECT_CALL(context_manager_mock_, ShutDownBorealis()).Times(0);
+
+  monitor.SetShutdownDelayForTesting(base::TimeDelta::FromSeconds(0));
+  monitor.ShutdownWithDelay();
+
+  // I'm assuming this thread won't be idle for 99 seconds.
+  monitor.SetShutdownDelayForTesting(base::TimeDelta::FromSeconds(99));
+  monitor.ShutdownWithDelay();
+
+  task_environment_.RunUntilIdle();
+}
+
+TEST_F(BorealisShutdownMonitorTest, DeletingMonitorCancelsShutdowns) {
+  auto monitor = std::make_unique<BorealisShutdownMonitor>(profile());
+
+  EXPECT_CALL(context_manager_mock_, ShutDownBorealis()).Times(0);
+
+  monitor->SetShutdownDelayForTesting(base::TimeDelta::FromSeconds(0));
+  monitor->ShutdownWithDelay();
+  monitor.reset();
+
+  task_environment_.RunUntilIdle();
+}
+
+}  // namespace
+}  // namespace borealis