[scheduler] Delete task_cost_estimator_unittest.cc

It's not used anymore and doesn't even have a corresponding .gn entry.

R=skyostil@chromium.org

Change-Id: Ic069df8a5ab7e58950c269513ac4a2eedc3c11cf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1890079
Auto-Submit: Alexander Timin <altimin@chromium.org>
Commit-Queue: Sami Kyöstilä <skyostil@chromium.org>
Reviewed-by: Sami Kyöstilä <skyostil@chromium.org>
Cr-Commit-Position: refs/heads/master@{#710833}

third_party/blink/renderer/platform/scheduler/main_thread/task_cost_estimator_unittest.cc

-// Copyright 2015 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 "third_party/blink/renderer/platform/scheduler/main_thread/task_cost_estimator.h"
-
-#include <memory>
-
-#include "base/test/simple_test_tick_clock.h"
-#include "testing/gmock/include/gmock/gmock.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace blink {
-namespace scheduler {
-
-class TaskCostEstimatorTest : public testing::Test {
- public:
-  TaskCostEstimatorTest() = default;
-  ~TaskCostEstimatorTest() override = default;
-
-  base::SimpleTestTickClock clock_;
-};
-
-class TaskCostEstimatorForTest : public TaskCostEstimator {
- public:
-  TaskCostEstimatorForTest(const base::TickClock* clock,
-                           int sample_count,
-                           double estimation_percentile)
-      : TaskCostEstimator(clock, sample_count, estimation_percentile) {}
-};
-
-TEST_F(TaskCostEstimatorTest, BasicEstimation) {
-  TaskCostEstimatorForTest estimator(&clock_, 1, 100);
-  base::PendingTask task(FROM_HERE, base::Closure());
-
-  estimator.WillProcessTask(task);
-  clock_.Advance(base::TimeDelta::FromMilliseconds(500));
-  estimator.DidProcessTask(task);
-
-  EXPECT_EQ(base::TimeDelta::FromMilliseconds(500),
-            estimator.expected_task_duration());
-}
-
-TEST_F(TaskCostEstimatorTest, Clear) {
-  TaskCostEstimatorForTest estimator(&clock_, 1, 100);
-  base::PendingTask task(FROM_HERE, base::Closure());
-
-  estimator.WillProcessTask(task);
-  clock_.Advance(base::TimeDelta::FromMilliseconds(500));
-  estimator.DidProcessTask(task);
-
-  estimator.Clear();
-
-  EXPECT_EQ(base::TimeDelta(), estimator.expected_task_duration());
-}
-
-TEST_F(TaskCostEstimatorTest, NestedRunLoop) {
-  TaskCostEstimatorForTest estimator(&clock_, 1, 100);
-  base::PendingTask task(FROM_HERE, base::Closure());
-
-  // Make sure we ignore the tasks inside the nested run loop.
-  estimator.WillProcessTask(task);
-  estimator.WillProcessTask(task);
-  clock_.Advance(base::TimeDelta::FromMilliseconds(500));
-  estimator.DidProcessTask(task);
-  clock_.Advance(base::TimeDelta::FromMilliseconds(500));
-  estimator.DidProcessTask(task);
-
-  EXPECT_EQ(base::TimeDelta::FromMilliseconds(1000),
-            estimator.expected_task_duration());
-}
-
-}  // namespace scheduler
-}  // namespace blink