Bug: angleproject:2471

Mock ICD json file was only being copied to angledata when "build all"
was done. This fix causes the json file to be copied anytime something
with a Vulkan dep is compiled.

Change-Id: Ic56ecf12ff5996d14bd2ed419f50b2362453b939
Reviewed-on: https://chromium-review.googlesource.com/1020233
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>