Also use the requested renderer to initialize expectations.

BUG=angleproject:1442

Change-Id: Idf54072dac5f7ad9deea70e97d65e36a6e883b1c
Reviewed-on: https://chromium-review.googlesource.com/407802
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>