This reverts commit 755a9317.

Reason for revert: Broke local win build. crbug.com/797253

Original change's description:
> Re-land "Vulkan: Roll loader/validation layers SDK. (2/2)"
> 
> Re-landing with upstream fixes to the layers so they no longer
> need to copy the parameter validation errors to the current
> working directory of the layer generation. Also includes fixes
> for the GCC build.
> 
> This hasn't been updated in a while, so there are many changes.
> It should also include better validation for memory barriers.
> 
> Also includes updated builds for SPIRV Tools and glslang.
> A few pull requests need to land before landing this in ANGLE.
> 
> This second step re-enables Vulkan and includes the updated build.
> 
> Includes a workaround for parameter_validation.h no longer being
> auto-generated, and the stale file clobbering the build.
> 
> Also includes a fix for an incorrect memory barrier.
> 
> Bug: angleproject:2237
> Change-Id: I1ed87ecfa84f51ee1edf6a8581d9b3c8f9a6f26e
> Reviewed-on: https://chromium-review.googlesource.com/834429
> Commit-Queue: Jamie Madill <jmadill@chromium.org>
> Reviewed-by: Jamie Madill <jmadill@chromium.org>

TBR=fjhenigman@chromium.org,jmadill@chromium.org

Change-Id: I605d72207d64c7d0853678595e255b74ad69d887
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: angleproject:2237
Reviewed-on: https://chromium-review.googlesource.com/842918Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Zhenyao Mo <zmo@chromium.org>