Roll src/third_party/glslang/src 83af46951202..a4af7676feb0 (1 commits)

https://chromium.googlesource.com/external/github.com/KhronosGroup/glslang/+log/83af46951202..a4af7676feb0

git log 83af46951202..a4af7676feb0 --date=short --first-parent --format='%ad %ae %s'
2019-12-03 johnkslang@users.noreply.github.com Merge pull request #2004 from ianromanick/document-other-test-requirements

Created with:
  gclient setdep -r src/third_party/glslang/src@a4af7676feb0

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/glslang-chromium-autoroll
Please CC radial-bots+chrome-roll@google.com,geofflang@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

Bug: None
Tbr: radial-bots+chrome-roll@google.com,geofflang@google.com
Change-Id: I20011820442d45267e195f31decbc68a808fb2cc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1948357Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#720860}

DEPS

@@ -959,7 +959,7 @@ deps = {
   },
 
   'src/third_party/glslang/src':
-    Var('chromium_git') + '/external/github.com/KhronosGroup/glslang.git' + '@' + '83af46951202c0f8cfdbe786b102805d9905b62d',
+    Var('chromium_git') + '/external/github.com/KhronosGroup/glslang.git' + '@' + 'a4af7676feb011d61b1dfa8915bd41d9c5aaf22a',
 
   'src/third_party/google_toolbox_for_mac/src': {
       'url': Var('chromium_git') + '/external/github.com/google/google-toolbox-for-mac.git' + '@' + Var('google_toolbox_for_mac_revision'),