Roll third_party/externals/libgifcodec ed218be1..38d9c73f (2 commits)

https://skia.googlesource.com/libgifcodec/+log/ed218be1..38d9c73f

git log ed218be1..38d9c73f --date=short --first-parent --format='%ad %ae %s'
2019-12-11 mtklein@google.com don't include unused header
2019-12-02 halcanary@google.com Add README.chromium file

Change-Id: I593bd8fd5e44c772b68a9324c55c6af2648fc56d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/259316
Commit-Queue: Hal Canary <halcanary@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Auto-Submit: Hal Canary <halcanary@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
1 file changed