Roll src/third_party/swiftshader 7a7f630ffbad..860369fc431e (5 commits)

https://swiftshader.googlesource.com/SwiftShader.git/+log/7a7f630ffbad..860369fc431e

git log 7a7f630ffbad..860369fc431e --date=short --no-merges --format='%ad %ae %s'
2019-09-16 sugoi@google.com Enable vertexPipelineStoresAndAtomics feature
2019-09-16 sugoi@google.com Robust buffer access for vertex inputs
2019-09-16 sugoi@google.com Prevent extra vertices from being processed
2019-09-16 sugoi@google.com Point vertex processing optimization
2019-09-16 swiftshader.regress@gmail.com Regres: Update test lists @ 30847688

Created with:
  gclient setdep -r src/third_party/swiftshader@860369fc431e

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/swiftshader-chromium-autoroll
Please CC swiftshader-team+autoroll@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_optional_gpu_tests_rel;luci.chromium.try:linux_chromium_msan_rel_ng;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
TBR=swiftshader-team+autoroll@google.com

Bug: None
Change-Id: Ife9478ae8445a9d344ceb110bfc88ca02e7b52b2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1807136Reviewed-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@{#696980}

DEPS

@@ -178,7 +178,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling SwiftShader
   # and whatever else without interference from each other.
-  'swiftshader_revision': '7a7f630ffbad1044c65c06ec08e5b7fa236666e2',
+  'swiftshader_revision': '860369fc431e8510f974799961083b42d01cfa8b',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling PDFium
   # and whatever else without interference from each other.