Fixing typo in a comment.

Bug: None
Change-Id: I6efa80f6e17eb0cb9f87d76e6321518842902ec4
No-Try: True
Reviewed-on: https://webrtc-review.googlesource.com/32820
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21269}

test/single_threaded_task_queue.cc

@@ -110,7 +110,7 @@ void SingleThreadedTaskQueueForTesting::RunLoop() {
     std::unique_ptr<QueuedTask> queued_task;
 
     // An empty queue would lead to sleeping until the queue becoems non-empty.
-    // A queue where the earliest task is shceduled for later than now, will
+    // A queue where the earliest task is scheduled for later than now, will
     // lead to sleeping until the time of the next scheduled task (or until
     // more tasks are scheduled).
     int wait_time = rtc::Event::kForever;