Roll src/third_party/libyuv/ 6866adbec..19d71f6b3 (8 commits)

https://chromium.googlesource.com/libyuv/libyuv.git/+log/6866adbec5af..19d71f6b351f

$ git log 6866adbec..19d71f6b3 --date=short --no-merges --format='%ad %ae %s'
2020-10-24 libyuv-ci-autoroll-builder Roll chromium_revision e812106b..df9aecfc (817907:820568)
2020-10-16 libyuv-ci-autoroll-builder Roll chromium_revision 48924233..e812106b (815587:817907)
2020-10-13 fbarchard UVScale down use AVX2 and Neon for aarch32
2020-10-13 fbarchard UVScale down by 4 use SSSE3/NEON
2020-10-12 fbarchard 2x down sample for UV planes ported to SSSE3 / NEON
2020-10-09 libyuv-ci-autoroll-builder Roll chromium_revision ccec2ad0..48924233 (811963:815587)
2020-10-02 fbarchard I420ToARGB prototype added to convert_from.h
2020-10-01 fbarchard scale neon adjust PRFM instruction to co-issue with math

Created with:
  roll-dep src/third_party/libyuv

Bug: None
Change-Id: I3b0edcc78471ee3dc5701f40b07acf6b97560664
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2502469
Commit-Queue: Frank Barchard <fbarchard@chromium.org>
Reviewed-by: Frank Barchard <fbarchard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821264}

DEPS

@@ -1171,7 +1171,7 @@ deps = {
     Var('chromium_git') + '/webm/libwebm.git' + '@' + '51ca718c3adf0ddedacd7df25fe45f67dc5a9ce1',
 
   'src/third_party/libyuv':
-    Var('chromium_git') + '/libyuv/libyuv.git' + '@' + '6866adbec5af1b3c66d1ace334a43ad61e6bb268',  # from r1714
+    Var('chromium_git') + '/libyuv/libyuv.git' + '@' + '19d71f6b351fe992ae34b114eebd872c383a6bdb',  # from r1714
 
   'src/third_party/lighttpd': {
       'url': Var('chromium_git') + '/chromium/deps/lighttpd.git' + '@' + Var('lighttpd_revision'),