Check result of D3D11 map operation in Blit11::copyAndConvert.
Check result of D3D11 map operation in Blit11::copyAndConvert.

BUG=825503

Change-Id: I407ded1970266bc4fa975850d5700544b9f17b4b
Reviewed-on: https://chromium-review.googlesource.com/980693
Reviewed-by: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>
Commit-Queue: Geoff Lang <b6fc25fe0362055230985c05cbfa8adb741ccc0f@chromium.org>

ppy/angle,ppy/angle,ppy/angle,ppy/angle