Roll third_party/externals/angle2 cb7e738..31e36a6 (2 commits)

https://chromium.googlesource.com/angle/angle.git/+log/cb7e7387e61f..31e36a631345

git log cb7e738..31e36a6 --date=short --first-parent --format='%ad %ae %s'
2020-03-23 lexa.knyazev@gmail.com Reland "Refactor BitCount"
2020-03-23 angle-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/SwiftShader 1c9f24263e6c..22d73d15e778 (1 commits)

Created with:
  gclient setdep -r third_party/externals/angle2@31e36a631345

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/angle-skia-autoroll
Please CC robertphillips@google.com,brianosman@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/skia.primary:Build-Debian9-Clang-x86_64-Release-ANGLE;skia/skia.primary:Test-Win10-Clang-AlphaR2-GPU-RadeonR9M470X-x86_64-Debug-All-ANGLE;skia/skia.primary:Test-Win10-Clang-Golo-GPU-QuadroP400-x86_64-Debug-All-ANGLE;skia/skia.primary:Test-Win10-Clang-NUC5i7RYH-GPU-IntelIris6100-x86_64-Debug-All-ANGLE;skia/skia.primary:Test-Win10-Clang-NUC6i5SYK-GPU-IntelIris540-x86_64-Debug-All-ANGLE;skia/skia.primary:Test-Win10-Clang-NUC8i5BEK-GPU-IntelIris655-x86_64-Debug-All-ANGLE;skia/skia.primary:Test-Win10-Clang-NUCD34010WYKH-GPU-IntelHD4400-x86_64-Debug-All-ANGLE
Bug: None
Tbr: robertphillips@google.com,brianosman@google.com
Change-Id: Ic34429611278eb739560390ff19d207b9ad40ab5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/278486
Reviewed-by: skia-autoroll <skia-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: skia-autoroll <skia-autoroll@skia-public.iam.gserviceaccount.com>

DEPS

@@ -7,7 +7,7 @@ vars = {
 deps = {
   "buildtools"                            : "https://chromium.googlesource.com/chromium/buildtools.git@505de88083136eefd056e5ee4ca0f01fe9b33de8",
   "common"                                : "https://skia.googlesource.com/common.git@9737551d7a52c3db3262db5856e6bcd62c462b92",
-  "third_party/externals/angle2"          : "https://chromium.googlesource.com/angle/angle.git@cb7e7387e61f591f2eaf2e899af64a0cb2446dbf",
+  "third_party/externals/angle2"          : "https://chromium.googlesource.com/angle/angle.git@31e36a6313457e32bcb7da0a85ed5a73504dd231",
   # Dawn requires jinja2 and markupsafe for the code generator.
   # When the Dawn revision is updated these should be updated from the Dawn DEPS as well.
   "third_party/externals/dawn"            : "https://dawn.googlesource.com/dawn.git@604072bc2ed01018eb03bcbbf9d94042f679af63",