Roll VK Headers/Tools/Loader/ValidationLayers forward.
There's a build improvement as well as many new checks.

Added new source file dep, convert_to_renderpass2.cpp, used by core_
validation for added RenderPass2 checks.

Bug: angleproject:2937
Bug: chromium:845519
Change-Id: Id5c30c5bfc684c365a8ad97c3289bccc02afb3b3
Reviewed-on: https://chromium-review.googlesource.com/c/1305673Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Tobin Ehlis <tobine@google.com>