Roll third_party/externals/swiftshader d9ed1c2..31edef7 (3 commits)

https://swiftshader.googlesource.com/SwiftShader.git/+log/d9ed1c2732ba..31edef751a8d

git log d9ed1c2..31edef7 --date=short --no-merges --format='%ad %ae %s'
2019-11-09 chrisforbes@google.com Update deqp to vulkan-cts-1.1.6.1
2019-11-08 chrisforbes@google.com Fix PointCoord builtin
2019-11-08 bclayton@google.com Kokoro: Allow 'Fixes:' in bug check

Created with:
  gclient setdep -r third_party/externals/swiftshader@31edef751a8d

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/swiftshader-skia-autoroll
Please CC halcanary@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=skia.primary:Test-Debian9-Clang-GCE-GPU-SwiftShader-x86_64-Debug-All-SwiftShader
Bug: None
TBR=halcanary@google.com
Change-Id: Ia990eca315b394e52228ec9787426321eea4a6a5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/253837
Reviewed-by: skia-autoroll <skia-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: skia-autoroll <skia-autoroll@skia-public.iam.gserviceaccount.com>

Author: skia-autoroll

DEPS

@@ -30,7 +30,7 @@ deps = {
   "third_party/externals/spirv-cross"     : "https://chromium.googlesource.com/external/github.com/KhronosGroup/SPIRV-Cross@53ab2144b90abede33be5161aec5dfc94ddc3caf",
   "third_party/externals/spirv-headers"   : "https://skia.googlesource.com/external/github.com/KhronosGroup/SPIRV-Headers.git@29c11140baaf9f7fdaa39a583672c556bf1795a1",
   "third_party/externals/spirv-tools"     : "https://skia.googlesource.com/external/github.com/KhronosGroup/SPIRV-Tools.git@0c4feb643b89d1792b02f7cbef315e9d95633bd7",
-  "third_party/externals/swiftshader"     : "https://swiftshader.googlesource.com/SwiftShader@d9ed1c2732ba9b1bd36461367d348e3030043a25",
+  "third_party/externals/swiftshader"     : "https://swiftshader.googlesource.com/SwiftShader@31edef751a8d8428db1fc9e0f68c345ab987811f",
   #"third_party/externals/v8"              : "https://chromium.googlesource.com/v8/v8.git@5f1ae66d5634e43563b2d25ea652dfb94c31a3b4",
   "third_party/externals/wuffs"           : "https://skia.googlesource.com/external/github.com/google/wuffs.git@4080840928c0b05a80cda0d14ac2e2615f679f1a",
   "third_party/externals/zlib"            : "https://chromium.googlesource.com/chromium/src/third_party/zlib@47af7c547f8551bd25424e56354a2ae1e9062859",