Support new syntax of attr()
Support attr()'s new syntax function according to CSS Values 5 spec [0]:
attr() = attr( ? , ?)
This CL only implements the basic attr() support and does not include
security concerns handling, described in [1].
Android Binary Size (arm64 high end) (TrichromeLibrary64.apk) has
increased by 72,820 bytes with this commit, see detailed SuperSize HTML
Diff [2]. This is unavoidable change to support attr()'as extended
capabilities.
[0] https://drafts.csswg.org/css-values-5/#attr-notation
[1] w3c/csswg-drafts#5092
[2] https://chrome-supersize.firebaseapp.com/viewer.html?load_url=https%3A%2F%2Fstorage.googleapis.com%2Fchrome-supersize%2Foneoffs%2F5d767292566fc8a703add425aec266384201f481_0c795997696df0aefa7166aadf631be05995aac3.sizediff
Bug: 40320391
Change-Id: I6703ea6a6e59cec7579dce0df6e411de238361f6
Binary-Size: See commit description.
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5660057
Reviewed-by: Anders Hartvoll Ruud andruud@chromium.org
Commit-Queue: Munira Tursunova moonira@google.com
Cr-Commit-Position: refs/heads/main@{#1323782}