Twitter-famous NOOP bug.

Between patch set 4 and patch set 5 in
https://codereview.webrtc.org/2865113002/, a line consisting of a
single 'std::move(task);' was added. The reason we will never know,
because the author will not tell. The superfluous line would have gone
unnoticed except for occasional raised eyebrows of casual code
readers.

The Visual Studio compiler now sees lines that have no effect. Which
was announced to the world in the tweet
https://twitter.com/StephanTLavavej/status/924011366943354880
achieving 27 likes and 6 retweets.

Bug: webrtc:8463
Change-Id: Iac49bc4153254b6cfe99f609da28eb4f43ff765e
Reviewed-on: https://webrtc-review.googlesource.com/21324
Reviewed-by: Sam Zackrisson <saza@webrtc.org>
Commit-Queue: Alex Loiko <aleloi@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20616}
diff --git a/modules/audio_processing/aec_dump/aec_dump_impl.cc b/modules/audio_processing/aec_dump/aec_dump_impl.cc
index 8fe7b74..594bf85 100644
--- a/modules/audio_processing/aec_dump/aec_dump_impl.cc
+++ b/modules/audio_processing/aec_dump/aec_dump_impl.cc
@@ -117,7 +117,6 @@
 void AecDumpImpl::WriteCaptureStreamMessage() {
   auto task = capture_stream_info_.GetTask();
   RTC_DCHECK(task);
-  std::move(task);
   worker_queue_->PostTask(std::unique_ptr<rtc::QueuedTask>(std::move(task)));
   capture_stream_info_.SetTask(CreateWriteToFileTask());
 }