Vulkan: Disable warning in Mock ICD. We were missing a "no chromium code" config in the mock ICD. This was causing a build error, but the build error was mostly invisible because the mock ICD wasn't being built by default. Fix this by including it in the angle_vulkan target. Bug: angleproject:2482 Change-Id: I417d3fbf6a4acd93c06bab61967409730c2ea4ed Reviewed-on: https://chromium-review.googlesource.com/1012497 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Jamie Madill <jmadill@chromium.org>