Roll SPIRV-Tools from 726af6f78f80 to e8ce4355ae1c (9 revisions)

https://chromium.googlesource.com/external/github.com/KhronosGroup/SPIRV-Tools.git/+log/726af6f78f80..e8ce4355ae1c

2020-09-15 andreperezmaselco.developer@gmail.com spirv-fuzz: Add bit instruction synonym transformation (#3775)
2020-09-15 vasniktel@gmail.com spirv-fuzz: Skip unreachable blocks (#3729)
2020-09-15 afdx@google.com Fix build errors (#3804)
2020-09-15 vasniktel@gmail.com spirv-fuzz: Handle invalid ids in fact manager (#3742)
2020-09-15 vasniktel@gmail.com spirv-fuzz: Support memory instructions MoveInstructionDown (#3700)
2020-09-15 stefanomil@google.com spirv-fuzz: Pass submanagers to other submanagers when necessary (#3796)
2020-09-15 stefanomil@google.com spirv-fuzz: Transformation to flatten conditional branch (#3667)
2020-09-14 46493288+sfricke-samsung@users.noreply.github.com spirv-val: Add BaseInstance, BaseVertex, DrawIndex, and ViewIndex (#3782)
2020-09-14 dnovillo@google.com Properly mark IR changed if instruction folder creates more than one constant. (#3799)

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,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/+doc/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,jmadill@google.com
Change-Id: I5dfd8b4c49b7783fd25f375eacba608e766ab12e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2413401Reviewed-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@{#807393}

DEPS

@@ -302,7 +302,7 @@ 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': '726af6f78f80988271c8b558ae9cc84fa5a65016',
+  'spv_tools_revision': 'e8ce4355ae1c485864d0fc0f973a6d0a433d9ff0',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.