From the spec (2.3.1 Data Conversion For State-Setting Commands):
"Validation of values performed by state-setting commands is performed
after conversion, unless specified otherwise for a specific command."

BUG=783574

Change-Id: I9edf585a17489ad284bc85a1c3c2236b53ee34d9
Reviewed-on: https://chromium-review.googlesource.com/766569Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>