TaskScheduler: Match behavior of SequencedWorkerPool in RunsTasksOnCurrentThread().

base/task_scheduler/scheduler_worker_pool_impl_unittest.cc

Index: base/task_scheduler/scheduler_worker_pool_impl_unittest.cc
diff --git a/base/task_scheduler/scheduler_worker_pool_impl_unittest.cc b/base/task_scheduler/scheduler_worker_pool_impl_unittest.cc
index bbc6723c6671adeea5dab6f9fd9b8fc7d74073d2..abf63ea781861d88ca6d744ff8dd7f4904ef5f5d 100644
--- a/base/task_scheduler/scheduler_worker_pool_impl_unittest.cc
+++ b/base/task_scheduler/scheduler_worker_pool_impl_unittest.cc
@@ -327,6 +327,29 @@ TEST_P(TaskSchedulerWorkerPoolImplTest, PostDelayedTask) {
   task_ran.Wait();
 }
 
+// Verify that the RunsTasksOnCurrentThread() method of a SEQUENCED TaskRunner
+// returns false when called from a task that isn't part of the sequence.
+TEST_P(TaskSchedulerWorkerPoolImplTest, SequencedRunsTasksOnCurrentThread) {
+  scoped_refptr<TaskRunner> task_runner(
+      worker_pool_->CreateTaskRunnerWithTraits(TaskTraits(), GetParam()));
+  scoped_refptr<TaskRunner> sequenced_task_runner(
+      worker_pool_->CreateTaskRunnerWithTraits(TaskTraits(),
+                                               ExecutionMode::SEQUENCED));
+
+  WaitableEvent task_ran(WaitableEvent::ResetPolicy::MANUAL,
+                         WaitableEvent::InitialState::NOT_SIGNALED);
+  task_runner->PostTask(
+      FROM_HERE,
+      Bind(
+          [](scoped_refptr<TaskRunner> sequenced_task_runner,
+             WaitableEvent* task_ran) {
+            EXPECT_FALSE(sequenced_task_runner->RunsTasksOnCurrentThread());

[robliao, 2016/09/14 15:50:27]

We only ever check for false for RunsTasksOnCurrentThread. Let's add a true
check as well.

[fdoray, 2016/09/14 16:56:44]

This is already tested by
https://cs.chromium.org/chromium/src/base/task_scheduler/test_task_factory.cc...
EXPECT_TRUE(task_runner_->RunsTasksOnCurrentThread());

(Many TaskSchedulerWorkerPoolImplTest use TestTaskFactory)

[robliao, 2016/09/14 17:20:42]

Gotcha. Let's add a quick comment about that here since we explicitly test for
false here.

[fdoray, 2016/09/15 12:19:01]

Done. Added comment about TestTaskFactory in this test.

+            task_ran->Signal();
+          },
+          sequenced_task_runner, Unretained(&task_ran)));
+  task_ran.Wait();
+}
+
 INSTANTIATE_TEST_CASE_P(Parallel,
                         TaskSchedulerWorkerPoolImplTest,
                         ::testing::Values(ExecutionMode::PARALLEL));