Add test for posting a single task to the worker pool

test/unittests/libplatform/worker-thread-unittest.cc

Index: test/unittests/libplatform/worker-thread-unittest.cc
diff --git a/test/unittests/libplatform/worker-thread-unittest.cc b/test/unittests/libplatform/worker-thread-unittest.cc
index 175b31166691cb75644eafb807973237ffd7c483..f0b41e78dd8c22ad88260c25c6184743bd18fba0 100644
--- a/test/unittests/libplatform/worker-thread-unittest.cc
+++ b/test/unittests/libplatform/worker-thread-unittest.cc
@@ -44,5 +44,21 @@ TEST(WorkerThreadTest, Basic) {
   queue.Terminate();
 }
 
+TEST(WorkerThreadTest, PostSingleTask) {
+  TaskQueue queue;
+  WorkerThread thread1(&queue);
+  WorkerThread thread2(&queue);
+
+  InSequence s;
+  StrictMock<MockTask>* task = new StrictMock<MockTask>;
+  EXPECT_CALL(*task, Run());
+  EXPECT_CALL(*task, Die());
+  queue.Append(task);
+
+  // The next call should not time out.
+  queue.BlockUntilQueueEmptyForTesting();
+  queue.Terminate();
+}
+
 }  // namespace platform
 }  // namespace v8