ScheduleYield was always called after GetData regardless of it's result.  This
meant that we would successfully get the data but still sleep the thread

BUG=667979

Change-Id: Iecba0ae5cacef64a1080bbd89ce352bc4f281359
Reviewed-on: https://chromium-review.googlesource.com/437636Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>