Roll src/third_party/SPIRV-Tools/src 4517c7b883c5..ec12de913124 (3 commits)

https://chromium.googlesource.com/external/github.com/KhronosGroup/SPIRV-Tools.git/+log/4517c7b883c5..ec12de913124

git log 4517c7b883c5..ec12de913124 --date=short --no-merges --format='%ad %ae %s'
2019-10-27 afdx@google.com spirv-fuzz: rename class, and fix bug related to dominance (#2990)
2019-10-25 afdx@google.com spirv-fuzz: Rework management of data synonyms (#2989)
2019-10-25 afdx@google.com spirv-fuzz: add class to represent equivalence relation (#2988)

Created with:
  gclient setdep -r src/third_party/SPIRV-Tools/src@ec12de913124

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,ynovikov@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,ynovikov@google.com

Bug: None
Change-Id: Iaf5bf4af6f25f4a25653e81bd823e0a23a3fc00d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1883062Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#709950}

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': '4517c7b883c56d9d1ef34f67b42fedd3f008f3dd',
+  'spv_tools_revision': 'ec12de9131244a076c34ddca2e8d7451288be7e1',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.