Reland "[css-grid] Clear the override width for computing percent margins"

[chromium-wpt-export-bot]

This is a reland of a445d168b9f54cc8902f8bac8da3bc490e441059..
The original patch has been reverted due to a performance regression,
described in bug #1002700.

Additionally, this patch solves some cases not covered by the original patch,
specifically when using 'non-auto' values for the grid item's min-width
property. It also provides additional regressions tests.

Finally, the performance regression is solved by checking out whether the
grid item needs layout before considering to clear the Override size.

Original change's description:

[css-grid] Clear the override width for computing percent margins

When calculating the min-content contribution of a grid item of an auto
sized grid track we must consider the grid item's margin. When the grid
item's area is indefinite, a percent margin is resolved to zero.
However, when performing a relayout, the percent margin may be solved
against the previously computed grid area, since the grid item has
already an OverrideContainingBlockLogicalWidth value.

In order to re-compute the percent margin properly, we need to clear
the previously override value. It's important be careful of not
clearing the override value set during intrinsic size, since we need
it for the actual layout phase. Hence, we only reset the 'override'
value when we are executing a definite strategy.

Bug: 834643
Change-Id: Ib936b26bee1da76afbdc886eb775746e13d40988
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1782840
Commit-Queue: Javier Fernandez <jfernandez@igalia.com>
Reviewed-by: Christian Biesinger <cbiesinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#694849}

Bug: 834643, 942811
Change-Id: Id6fdf52fab471ebefecb2c087c086faf0e3f5dec
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1796323
Commit-Queue: Javier Fernandez <jfernandez@igalia.com>
Reviewed-by: Manuel Rego <rego@igalia.com>
Cr-Commit-Position: refs/heads/master@{#699290}

[wpt-pr-bot]

Already reviewed downstream.