ServiceImageRecommendationProvider: Don't fail on first validation error

The image suggestion API can return invalid results. That is OK --
instead of failing on first invalid result, keep going until we find
valid results. If there are no valid results, then we can return the
validation error(s).

Depends-On: I467dd2780338a7f4a3cc5f3c5a7e664a2ab1b82a
Bug: T312521
Change-Id: Iaa4a78b16aa223cd5f61bdf73dce7adfad697f38
(cherry picked from commit 494e9d20290fec2ec785ddc0d3b042a654d2d271)