Roll src/third_party/SPIRV-Tools/src 3cdd6444cf91..e8c3f9b0b463 (3 commits)

https://chromium.googlesource.com/external/github.com/KhronosGroup/SPIRV-Tools.git/+log/3cdd6444cf91..e8c3f9b0b463

git log 3cdd6444cf91..e8c3f9b0b463 --date=short --no-merges --format='%ad %ae %s'
2019-10-18 chris@chris-lamb.co.uk Ensure timestamp does not vary with timezone. (#2982)
2019-10-18 stevenperron@google.com Keep NOPs when comparing with original binary (#2931)
2019-10-18 alanbaker@google.com Check that derivatives operate on 32-bit values (#2983)

Created with:
  gclient setdep -r src/third_party/SPIRV-Tools/src@e8c3f9b0b463

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/spirv-tools-chromium-autoroll
Please CC radial-bots+chrome-roll@google.com,jonahr@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

CQ_INCLUDE_TRYBOTS=luci.chromium.try:android_angle_vk32_deqp_rel_ng;luci.chromium.try:android_angle_vk32_rel_ng;luci.chromium.try:android_angle_vk64_deqp_rel_ng;luci.chromium.try:android_angle_vk64_rel_ng;luci.chromium.try:linux_angle_deqp_rel_ng;luci.chromium.try:linux-angle-rel;luci.chromium.try:win-angle-rel-32;luci.chromium.try:win-angle-rel-64;luci.chromium.try:win-angle-deqp-rel-32;luci.chromium.try:win-angle-deqp-rel-64
TBR=radial-bots+chrome-roll@google.com,jonahr@google.com

Bug: None
Change-Id: I0b6fcbdf85cd103957df75aa29821f803919066d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1871335Reviewed-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@{#707755}

DEPS

@@ -290,7 +290,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'spv_tools_revision': '3cdd6444cf91a5d74007eb0685885f0512066c4d',
+  'spv_tools_revision': 'e8c3f9b0b463c24eab839c82332344ccaddfa19d',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.