[TaskScheduler] Support TaskRunnerHandles from parallel tasks.

base/task_scheduler/test_task_factory.cc

Index: base/task_scheduler/test_task_factory.cc
diff --git a/base/task_scheduler/test_task_factory.cc b/base/task_scheduler/test_task_factory.cc
index 3b4e7235f0128fdcf84f00508736cebbb3336b8f..1a8301c618b1955774b012c4fd9b2e3485ada2ef 100644
--- a/base/task_scheduler/test_task_factory.cc
+++ b/base/task_scheduler/test_task_factory.cc
@@ -10,8 +10,7 @@
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/synchronization/waitable_event.h"
-#include "base/threading/sequenced_task_runner_handle.h"
-#include "base/threading/thread_task_runner_handle.h"
+#include "base/threading/task_runner_handle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
@@ -58,21 +57,19 @@ void TestTaskFactory::RunTaskCallback(size_t task_index,
   // Verify TaskRunnerHandles are set as expected in the task's scope.
   switch (execution_mode_) {
     case ExecutionMode::PARALLEL:
-      EXPECT_FALSE(ThreadTaskRunnerHandle::IsSet());
-      EXPECT_FALSE(SequencedTaskRunnerHandle::IsSet());
+      EXPECT_FALSE(TaskRunnerHandle::HasSingleThreadTaskScope());
+      EXPECT_FALSE(TaskRunnerHandle::HasSequencedTaskScope());
       break;
     case ExecutionMode::SEQUENCED:
-      EXPECT_FALSE(ThreadTaskRunnerHandle::IsSet());
-      EXPECT_TRUE(SequencedTaskRunnerHandle::IsSet());
-      EXPECT_EQ(task_runner_, SequencedTaskRunnerHandle::Get());
+      EXPECT_FALSE(TaskRunnerHandle::HasSingleThreadTaskScope());
+      EXPECT_TRUE(TaskRunnerHandle::HasSequencedTaskScope());
+      EXPECT_EQ(task_runner_, TaskRunnerHandle::GetSequenced());
       break;
     case ExecutionMode::SINGLE_THREADED:
-      // SequencedTaskRunnerHandle inherits from ThreadTaskRunnerHandle so
-      // both are expected to be "set" in the SINGLE_THREADED case.
-      EXPECT_TRUE(ThreadTaskRunnerHandle::IsSet());
-      EXPECT_TRUE(SequencedTaskRunnerHandle::IsSet());
-      EXPECT_EQ(task_runner_, ThreadTaskRunnerHandle::Get());
-      EXPECT_EQ(task_runner_, SequencedTaskRunnerHandle::Get());
+      EXPECT_TRUE(TaskRunnerHandle::HasSingleThreadTaskScope());
+      EXPECT_TRUE(TaskRunnerHandle::HasSequencedTaskScope());
+      EXPECT_EQ(task_runner_, TaskRunnerHandle::GetSingleThreaded());
+      EXPECT_EQ(task_runner_, TaskRunnerHandle::GetSequenced());
       break;
   }