Fix poster not hiding correctly sometimes.

Seems we need to repaint always when the first frame is available, not
just in lazy load circumstances. This is a speculative fix, since I have
not been able to reproduce the issue locally.

BUG=982415,980897
R=sandersd

Change-Id: I318ebb03f749fab9112a592047d1c45b77ceed12
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1695829
Auto-Submit: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Dan Sanders <sandersd@chromium.org>
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#676199}

media/blink/webmediaplayer_impl.cc

@@ -3484,7 +3484,7 @@ void WebMediaPlayerImpl::OnFirstFrame(base::TimeTicks frame_time) {
   RecordTimingUMA("Media.TimeToFirstFrame", elapsed);
 
   // Needed to signal HTMLVideoElement that it should remove the poster image.
-  if (client_ && did_lazy_load_ && has_poster_)
+  if (client_ && has_poster_)
     client_->Repaint();
 }