Roll vulkan-validation-layers. (2/2) https://android.googlesource.com/platform/external/vulkan-validation-layers.git/+log/bcb80d06bbdc09..f47c534fee2f26f This CL re-enables Vulkan with the new build files. In particular, this roll contains a fix for a vs2017 signed/unsigned mismatch warning as error. BUG=chromium:683729 Change-Id: Id38e10f97702cac5a51ee194c81972861f15db21 Reviewed-on: https://chromium-review.googlesource.com/457278 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>