Roll src/third_party/ffmpeg/ be66dc5fd..23b2a15c2 (2 commits)

https://chromium.googlesource.com/chromium/third_party/ffmpeg.git/+log/be66dc5fd0e3..23b2a15c2595

$ git log be66dc5fd..23b2a15c2 --date=short --no-merges --format='%ad %ae %s'
2020-06-16 dalecurtis Updated patches.
2020-05-01 dalecurtis Use gcc/clang builtins for av_sat_(add|sub)_64_c if available.

Created with:
  roll-dep src/third_party/ffmpeg

TBR=sandersd

Bug: 819294
Change-Id: I3ddd82346248f4382db00180dc51b1c7cd2971d7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2247347Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#779456}

DEPS

@@ -900,7 +900,7 @@ deps = {
   },
 
   'src/third_party/ffmpeg':
-    Var('chromium_git') + '/chromium/third_party/ffmpeg.git' + '@' + 'be66dc5fd0e3c53646107b2dc5d7594a869ebdc6',
+    Var('chromium_git') + '/chromium/third_party/ffmpeg.git' + '@' + '23b2a15c2595925c8ec0d3be9a51ec3257281bd1',
 
   'src/third_party/flac':
     Var('chromium_git') + '/chromium/deps/flac.git' + '@' + 'af862024c8c8fa0ae07ced05e89013d881b00596',