Roll src/third_party/harfbuzz-ng/src/ 7686ff854..4c34478b2 (33 commits)

https://chromium.googlesource.com/external/github.com/harfbuzz/harfbuzz.git/+log/7686ff854bbb..4c34478b2849

Expected to fix these type of ClusterFuzz issues in which random
allocation failures are simulated as this set of changes handles
such failures more reliably.

$ git log 7686ff854..4c34478b2 --date=short --no-merges --format='%ad %ae %s'
2021-03-16 khaled [tests] Increase shape-fuzzer timeout
2021-03-16 khaled [ci] Use known working Ubuntu version
2021-03-16 khaled [ci] Avoid duplicate builds on pull requests
2021-03-15 behdad [ci] Switch back to c++2a
2021-03-15 behdad [buffer] Fix order of HB_INTERNAL HB_DISCARD
2021-03-15 behdad [ci] Remove more cruft
2021-03-15 behdad [ci] Don't test C++2a build
2021-03-15 behdad [test] Fix output format
2021-03-15 behdad [buffer] HB_NODISCARD next_glyph()
2021-03-15 behdad [buffer] Implement copy_glyph() in terms of output_info()
2021-03-15 behdad [buffer] Implement replace_glyph() in terms of replace_glyphs(1,1)
2021-03-15 behdad [buffer] Implement output_glyph() in terms of replace_glyphs(0,1)
2021-03-15 behdad [buffer] HB_NODISCARD output_glyph()
2021-03-15 khaled [ci] Don’t install meson from its master branch
2021-03-15 behdad [buffer] HB_NODISCARD output_info()
2021-03-15 behdad [buffer] HB_NODISCARD copy_glyph()
2021-03-15 behdad [buffer] HB_NODISCARD next_glyphs()
2021-03-15 behdad [buffer] HB_NODISCARD has_separate_output()
2021-03-15 behdad [buffer] HB_NODISCARD in_error()
2021-03-15 behdad [buffer] HB_NODISCARD shift_forward()
2021-03-15 behdad [buffer] HB_NODISCARD make_room_for()
2021-03-15 behdad [buffer] HB_NODISCARD ensure_glyphs() / ensure_unicode()
2021-03-15 behdad [buffer] HB_NODISCARD ensure_inplace()
2021-03-15 behdad [buffer] HB_NODISCARD move_to()
2021-03-15 behdad [buffer] HB_NODISCARD ensure()
2021-03-15 behdad [buffer] HB_NODISCARD enlarge()
2021-03-15 behdad [buffer] HB_NODISCARD replace_glyph()
2021-03-15 behdad [buffer] HB_NODISCARD replace_glyphs()
2021-03-15 behdad [buffer] Return success status from buffer ops that can fail
2021-03-15 behdad [hangul] Improve error handling
2021-03-15 behdad [hangul] Whitespace
2021-03-10 behdad [subset] Make ClassDef format2 .intersects() return false if range value 0
2021-03-08 corbett.dav Update hb-ot-tag-table.hh (#2890)

Created with:
  roll-dep src/third_party/harfbuzz-ng/src
R=bashi@chromium.org,behdad@chromium.org,bungeman@chromium.org,drott@chromium.org,eae@chromium.org,jshin@chromium.org,kojii@chromium.org

Change-Id: Ie33482bad6dabb3bbe5593e4f4efbcb05991932f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2764066
Commit-Queue: Dominik Röttsches <drott@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Auto-Submit: Dominik Röttsches <drott@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#863229}