commit db55c07a1e4751e04d7c30d094d25634231867e9
author Oriol Brufau <obrufau@igalia.com> Wed Oct 28 22:09:04 2020
committer Commit Bot <commit-bot@chromium.org> Wed Oct 28 22:09:04 2020
tree a47c4dd38651435f25b8e6a387ac5dd33975922f
parent 87eae6df4307977cb553e0d985065669d28d145d

[css-grid] Prevent FindUsedFlexFraction from iterating items twice

IndefiniteSizeStrategy::FindUsedFlexFraction needs to iterate all grid
items that cross a flexible track. To do so it, takes the indices of the
flex tracks, and for each one it uses GridIterator to iterate the items
in that track.

Then, to avoid processing the same item multiple times, it used to check
that the item started in the current flex track, not in a previous one.

However, this was insufficient: it wasn't taking into account that an
item can be in a single flex track, but span multiple tracks in the
other axis.

Therefore, this patch changes it to use the same approach as in
GridTrackSizingAlgorithm::ResolveIntrinsicTrackSizes, i.e. creates a
HashSet outside of the loop, and inserts each given grid item to it,
checking whether it's a new entry or not.

Bug: 1026275
Change-Id: Ia0327e0459f2398de84b27851be53867f9be5f7a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2506210
Reviewed-by: Manuel Rego <rego@igalia.com>
Reviewed-by: Javier Fernandez <jfernandez@igalia.com>
Commit-Queue: Oriol Brufau <obrufau@igalia.com>
Cr-Commit-Position: refs/heads/master@{#821910}