Remove renderer notifications of memory pressure.

chrome/browser/memory/tab_manager_unittest.cc

Index: chrome/browser/memory/tab_manager_unittest.cc
diff --git a/chrome/browser/memory/tab_manager_unittest.cc b/chrome/browser/memory/tab_manager_unittest.cc
index a3621c1664b72299ee49daa1673b18d42ca76f31..6cf646f66495148a0ec8e04602a15fa2008ece96 100644
--- a/chrome/browser/memory/tab_manager_unittest.cc
+++ b/chrome/browser/memory/tab_manager_unittest.cc
@@ -31,7 +31,6 @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/mock_render_process_host.h"
 #include "content/public/test/web_contents_tester.h"
-#include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "url/gurl.h"
 
@@ -86,95 +85,6 @@ class MockTabStripModelObserver : public TabStripModelObserver {
   DISALLOW_COPY_AND_ASSIGN(MockTabStripModelObserver);
 };
 
-// A mock task runner. This isn't directly a TaskRunner as the reference
-// counting confuses gmock.
-class LenientMockTaskRunner {
- public:
-  LenientMockTaskRunner() {}
-  MOCK_METHOD2(PostDelayedTask,
-               bool(const tracked_objects::Location&, base::TimeDelta));
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(LenientMockTaskRunner);
-};
-using MockTaskRunner = testing::StrictMock<LenientMockTaskRunner>;
-
-// Represents a pending task.
-using Task = std::pair<base::TimeTicks, base::OnceClosure>;
-
-// Comparator used for sorting Task objects. Can't use std::pair's default
-// comparison operators because Closure's are comparable.
-struct TaskComparator {
-  bool operator()(const Task& t1, const Task& t2) const {
-    // Reverse the sort order so this can be used with a min-heap.
-    return t1.first > t2.first;
-  }
-};
-
-// A TaskRunner implementation that delegates to a MockTaskRunner for asserting
-// on task insertion order, and which stores tasks for actual later execution.
-class TaskRunnerProxy : public base::TaskRunner {
- public:
-  TaskRunnerProxy(MockTaskRunner* mock,
-                  base::SimpleTestTickClock* clock)
-      : mock_(mock), clock_(clock) {}
-  bool RunsTasksInCurrentSequence() const override { return true; }
-  bool PostDelayedTask(const tracked_objects::Location& location,
-                       base::OnceClosure closure,
-                       base::TimeDelta delta) override {
-    mock_->PostDelayedTask(location, delta);
-    base::TimeTicks when = clock_->NowTicks() + delta;
-    tasks_.push_back(Task(when, std::move(closure)));
-    // Use 'greater' comparator to make this a min heap.
-    std::push_heap(tasks_.begin(), tasks_.end(), TaskComparator());
-    return true;
-  }
-
-  // Runs tasks up to the current time. Returns the number of tasks executed.
-  size_t RunTasks() {
-    base::TimeTicks now = clock_->NowTicks();
-    size_t count = 0;
-    while (!tasks_.empty() && tasks_.front().first <= now) {
-      std::move(tasks_.front().second).Run();
-      std::pop_heap(tasks_.begin(), tasks_.end(), TaskComparator());
-      tasks_.pop_back();
-      ++count;
-    }
-    return count;
-  }
-
-  // Advances the clock and runs the next task in the queue. Can run more than
-  // one task if multiple tasks have the same scheduled time.
-  size_t RunNextTask() {
-    // Get the time of the next task that can possibly run.
-    base::TimeTicks when = tasks_.front().first;
-
-    // Advance the clock to exactly that time.
-    base::TimeTicks now = clock_->NowTicks();
-    if (now < when) {
-      base::TimeDelta delta = when - now;
-      clock_->Advance(delta);
-    }
-
-    // Run whatever tasks are now eligible to run.
-    return RunTasks();
-  }
-
-  size_t size() const { return tasks_.size(); }
-
- private:
-  ~TaskRunnerProxy() override {}
-
-  MockTaskRunner* mock_;
-  base::SimpleTestTickClock* clock_;
-
-  // A min-heap of outstanding tasks.
-  using Task = std::pair<base::TimeTicks, base::OnceClosure>;
-  std::vector<Task> tasks_;
-
-  DISALLOW_COPY_AND_ASSIGN(TaskRunnerProxy);
-};
-
 enum TestIndicies {
   kSelected,
   kAutoDiscardable,
@@ -188,19 +98,15 @@ enum TestIndicies {
   kOldButPinned,
   kInternalPage,
 };
+
 }  // namespace
 
-class LenientTabManagerTest : public ChromeRenderViewHostTestHarness {
+class TabManagerTest : public ChromeRenderViewHostTestHarness {
  public:
   WebContents* CreateWebContents() {
     return WebContents::Create(WebContents::CreateParams(profile()));
   }
-
-  MOCK_METHOD2(NotifyRendererProcess,
-               void(const content::RenderProcessHost*,
-                    base::MemoryPressureListener::MemoryPressureLevel));
 };
-using TabManagerTest = testing::StrictMock<LenientTabManagerTest>;
 
 // TODO(georgesak): Add tests for protection to tabs with form input and
 // playing audio;
@@ -508,168 +414,6 @@ TEST_F(TabManagerTest, CanOnlyDiscardOnce) {
 }
 #endif  // defined(OS_WIN) || defined(OS_MACOSX)
 
-namespace {
-
-using MemoryPressureLevel = base::MemoryPressureListener::MemoryPressureLevel;
-
-// Function that always indicates the absence of memory pressure.
-MemoryPressureLevel ReturnNoPressure() {
-  return base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE;
-}
-
-// Function that simply parrots back an externally specified memory pressure
-// level.
-MemoryPressureLevel ReturnSpecifiedPressure(
-    const MemoryPressureLevel* level) {
-  return *level;
-}
-
-}  // namespace
-
-// ChildProcessNotification is disabled on Chrome OS. crbug.com/588172.
-#if defined(OS_CHROMEOS)
-#define MAYBE_ChildProcessNotifications DISABLED_ChildProcessNotifications
-#else
-#define MAYBE_ChildProcessNotifications ChildProcessNotifications
-#endif
-
-// Ensure that memory pressure notifications are forwarded to child processes.
-TEST_F(TabManagerTest, MAYBE_ChildProcessNotifications) {
-  TabManager tm;
-
-  // Set up the tab strip.
-  TabStripDummyDelegate delegate;
-  TabStripModel tabstrip(&delegate, profile());
-
-  // Create test clock, task runner.
-  base::SimpleTestTickClock test_clock;
-  MockTaskRunner mock_task_runner;
-  scoped_refptr<TaskRunnerProxy> task_runner(
-      new TaskRunnerProxy(&mock_task_runner, &test_clock));
-
-  // Configure the TabManager for testing.
-  tabstrip.AddObserver(&tm);
-  tm.test_tab_strip_models_.push_back(
-      TabManager::TestTabStripModel(&tabstrip, false /* !is_app */));
-  tm.test_tick_clock_ = &test_clock;
-  tm.task_runner_ = task_runner;
-  tm.notify_renderer_process_ = base::Bind(
-      &TabManagerTest::NotifyRendererProcess, base::Unretained(this));
-
-  // Create two dummy tabs.
-  auto* tab0 = CreateWebContents();
-  auto* tab1 = CreateWebContents();
-  auto* tab2 = CreateWebContents();
-  tabstrip.AppendWebContents(tab0, true);   // Foreground tab.
-  tabstrip.AppendWebContents(tab1, false);  // Background tab.
-  tabstrip.AppendWebContents(tab2, false);  // Background tab.
-  const content::RenderProcessHost* renderer1 = tab1->GetRenderProcessHost();
-  const content::RenderProcessHost* renderer2 = tab2->GetRenderProcessHost();
-
-  // Make sure that tab2 has a lower priority than tab1 by its access time.
-  test_clock.Advance(base::TimeDelta::FromMilliseconds(1));
-  tab2->SetLastActiveTime(test_clock.NowTicks());
-  test_clock.Advance(base::TimeDelta::FromMilliseconds(1));
-  tab1->SetLastActiveTime(test_clock.NowTicks());
-
-  // Expect that the tab manager has not yet encountered memory pressure.
-  EXPECT_FALSE(tm.under_memory_pressure_);
-  EXPECT_EQ(0u, tm.notified_renderers_.size());
-
-  // Simulate a memory pressure situation that will immediately end. This should
-  // cause no notifications or scheduled tasks.
-  auto level = base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE;
-  tm.get_current_pressure_level_ = base::Bind(&ReturnNoPressure);
-  tm.OnMemoryPressure(level);
-  testing::Mock::VerifyAndClearExpectations(&mock_task_runner);
-  EXPECT_FALSE(tm.under_memory_pressure_);
-  EXPECT_EQ(0u, task_runner->size());
-  EXPECT_EQ(0u, tm.notified_renderers_.size());
-
-  // START OF MEMORY PRESSURE
-
-  // Simulate a memory pressure situation that persists. This should cause a
-  // task to be scheduled, and a background renderer to be notified.
-  tm.get_current_pressure_level_ = base::Bind(
-      &ReturnSpecifiedPressure, base::Unretained(&level));
-  EXPECT_CALL(mock_task_runner, PostDelayedTask(
-      testing::_,
-      base::TimeDelta::FromSeconds(tm.kRendererNotificationDelayInSeconds)));
-  EXPECT_CALL(*this, NotifyRendererProcess(renderer2, level));
-  tm.OnMemoryPressure(level);
-  testing::Mock::VerifyAndClearExpectations(&mock_task_runner);
-  testing::Mock::VerifyAndClearExpectations(this);
-  EXPECT_TRUE(tm.under_memory_pressure_);
-  EXPECT_EQ(1u, task_runner->size());
-  EXPECT_EQ(1u, tm.notified_renderers_.size());
-  EXPECT_EQ(1u, tm.notified_renderers_.count(renderer2));
-
-  // REPEATED MEMORY PRESSURE SIGNAL
-
-  // Simulate another memory pressure event. This should not cause any
-  // additional tasks to be scheduled, nor any further renderer notifications.
-  tm.OnMemoryPressure(level);
-  testing::Mock::VerifyAndClearExpectations(&mock_task_runner);
-  testing::Mock::VerifyAndClearExpectations(this);
-  EXPECT_TRUE(tm.under_memory_pressure_);
-  EXPECT_EQ(1u, task_runner->size());
-  EXPECT_EQ(1u, tm.notified_renderers_.size());
-
-  // FIRST SCHEDULED NOTIFICATION
-
-  // Run the scheduled task. This should cause another notification, but this
-  // time to the foreground tab. It should also cause another scheduled event.
-  EXPECT_CALL(mock_task_runner, PostDelayedTask(
-      testing::_,
-      base::TimeDelta::FromSeconds(tm.kRendererNotificationDelayInSeconds)));
-  EXPECT_CALL(*this, NotifyRendererProcess(renderer1, level));
-  EXPECT_EQ(1u, task_runner->RunNextTask());
-  testing::Mock::VerifyAndClearExpectations(&mock_task_runner);
-  testing::Mock::VerifyAndClearExpectations(this);
-  EXPECT_TRUE(tm.under_memory_pressure_);
-  EXPECT_EQ(1u, task_runner->size());
-  EXPECT_EQ(2u, tm.notified_renderers_.size());
-  EXPECT_EQ(1u, tm.notified_renderers_.count(renderer1));
-
-  // SECOND SCHEDULED NOTIFICATION
-
-  // Run the scheduled task. This should cause another notification, to the
-  // background tab. It should also cause another scheduled event.
-  EXPECT_CALL(mock_task_runner, PostDelayedTask(
-      testing::_,
-      base::TimeDelta::FromSeconds(tm.kRendererNotificationDelayInSeconds)));
-  EXPECT_CALL(*this, NotifyRendererProcess(renderer2, level));
-  EXPECT_EQ(1u, task_runner->RunNextTask());
-  testing::Mock::VerifyAndClearExpectations(&mock_task_runner);
-  testing::Mock::VerifyAndClearExpectations(this);
-  EXPECT_TRUE(tm.under_memory_pressure_);
-  EXPECT_EQ(1u, task_runner->size());
-  EXPECT_EQ(1u, tm.notified_renderers_.size());
-
-  // Expect that the background tab has been notified. The list of notified
-  // renderers maintained by the TabManager should also have been reset because
-  // the notification logic restarts after all renderers are notified.
-  EXPECT_EQ(1u, tm.notified_renderers_.count(renderer2));
-
-  // END OF MEMORY PRESSURE
-
-  // End the memory pressure condition and run the scheduled event. This should
-  // clean up the various state data. It should not schedule another event nor
-  // fire any notifications.
-  level = base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE;
-  EXPECT_EQ(1u, task_runner->RunNextTask());
-  testing::Mock::VerifyAndClearExpectations(&mock_task_runner);
-  testing::Mock::VerifyAndClearExpectations(this);
-  EXPECT_FALSE(tm.under_memory_pressure_);
-  EXPECT_EQ(0u, task_runner->size());
-  EXPECT_EQ(0u, tm.notified_renderers_.size());
-
-
-  // Clean up the tabstrip.
-  tabstrip.CloseAllTabs();
-  ASSERT_TRUE(tabstrip.empty());
-}
-
 TEST_F(TabManagerTest, DefaultTimeToPurgeInCorrectRange) {
   TabManager tab_manager;
   base::TimeDelta time_to_purge =