Roll src/third_party/glslang/src a959deb00750..834ee546f93d (1 commits)

https://chromium.googlesource.com/external/github.com/KhronosGroup/glslang/+log/a959deb00750..834ee546f93d

git log a959deb00750..834ee546f93d --date=short --no-merges --format='%ad %ae %s'
2019-10-17 johnkslang@users.noreply.github.com Merge pull request #1937 from jeffbolznv/volatile_atomics

Created with:
  gclient setdep -r src/third_party/glslang/src@834ee546f93d

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,jmadill@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

TBR=radial-bots+chrome-roll@google.com,jmadill@google.com

Bug: None
Change-Id: Icd6d999b7245ae7761cacce2cf8cd7d71e057486
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1866432Reviewed-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@{#707057}

DEPS

@@ -956,7 +956,7 @@ deps = {
   },
 
   'src/third_party/glslang/src':
-    Var('chromium_git') + '/external/github.com/KhronosGroup/glslang.git' + '@' + 'a959deb00750826fb087171d663947df550a3339',
+    Var('chromium_git') + '/external/github.com/KhronosGroup/glslang.git' + '@' + '834ee546f93d33a80fb2dea6fdef6764f8730b75',
 
   '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'),