layout: Store shared styles for table backgrounds in `SharedBackgroundStyle` (#36893)HEADmain

Table cells share background styles with their track and track group
boxes. When a track and track group style is repaired, this new data
structure will allow reparing the style of the cell `Fragment`s without
having to lay the table out again or walk through `Fragment`s and
individually repair their background styles.

Testing: This doesn't change behavior and is thus tested by existing
WPT tests.

Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>

0 files changed, 0 insertions, 0 deletions