retry absl
This time around, cut the absl deps down to just what's
needed to compile, link, and run AbseilTest.cpp.
Add basic absl::btree_map test.
Bug: skia:10165
Cq-Include-Trybots: skia/skia.primary:Build-Debian10-Clang-arm-Debug-Chromebook_GLES;skia/skia.primary:Test-Mac10.13-Clang-MacBookPro11.5-CPU-AVX2-x86_64-Release-All-TSAN
Change-Id: I53d632a04cba8dadd484b2c4d0ceefb314676486
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/286070
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
5 files changed