[mathml] Fix offset of vertical glyph assembly

When ShapeResult::CreateForStretchyMathOperator shapes vertical glyph
assemblies, the offset of each part is adjusted by the advance specified
in the corresponding MathGlyphVariantRecord table [1]. Note that this may be slightly different from the calculated ink height of the glyph,
but is faster to get. In any case the baselines of glyphs are used as a
reference when setting an offset in ShapeResults, so this CL changes the
adjustment to use the glyph ink ascent instead of the glyph ink height.

This CL fixes rendering issues for vertical stretchy MathML Operators
for fonts like Cambria Math that use non-zero ink descent for parts in
a glyph assembly.

StretchyOperatorShaperTest.GlyphVariants is tweaked to use an equivalent
stretchy.woff font (glyphs have zero ink descent) and a new test
StretchyOperatorShaperTest.GlyphVariantsCenteredOnBaseline is introduced
for a similar stretchy-centered-on-baseline.woff (glyphs have non-zero
and equal ink ascent/descent).

Finally, a WPT test is added to check that the painting of a vertical
glyph assembly with the two fonts above matches the location of their
bounding boxes.

[1] https://learn.microsoft.com/en-us/typography/opentype/spec/math

Bug: 1409380
Change-Id: I173c1cf461cebe3523e1a10aaf8d7b479bca03ad
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4197134
Commit-Queue: Frédéric Wang <fwang@igalia.com>
Reviewed-by: Dominik Röttsches <drott@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1098136}
10 files changed
tree: 01940fde0014c2d4ad38d2f1c26f0604174b41af
  1. android_webview/
  2. apps/
  3. ash/
  4. base/
  5. build/
  6. build_overrides/
  7. buildtools/
  8. cc/
  9. chrome/
  10. chromecast/
  11. chromeos/
  12. codelabs/
  13. components/
  14. content/
  15. courgette/
  16. crypto/
  17. dbus/
  18. device/
  19. docs/
  20. extensions/
  21. fuchsia_web/
  22. gin/
  23. google_apis/
  24. google_update/
  25. gpu/
  26. headless/
  27. infra/
  28. ios/
  29. ipc/
  30. media/
  31. mojo/
  32. native_client_sdk/
  33. net/
  34. pdf/
  35. ppapi/
  36. printing/
  37. remoting/
  38. rlz/
  39. sandbox/
  40. services/
  41. skia/
  42. sql/
  43. storage/
  44. styleguide/
  45. testing/
  46. third_party/
  47. tools/
  48. ui/
  49. url/
  50. weblayer/
  51. .clang-format
  52. .clang-tidy
  53. .eslintrc.js
  54. .git-blame-ignore-revs
  55. .gitattributes
  56. .gitignore
  57. .gn
  58. .mailmap
  59. .rustfmt.toml
  60. .vpython3
  61. .yapfignore
  64. BUILD.gn
  66. codereview.settings
  67. DEPS
  70. LICENSE.chromium_os
  71. OWNERS
  72. PRESUBMIT.py
  73. PRESUBMIT_test.py
  74. PRESUBMIT_test_mocks.py
  75. README.md

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