[css-grid] Clearing override sizes before running grid's layout logic.
Grid's layout logic manages two different override sizes; one it's
designed to implement the grid item's stretching behavior, identified
with the concept of 'overrideContentLogicalSize'; there is another
override size, known as overrideContainingBlockContentLogicalSize,
used to implement the Grid Area abstraction, which will behave as
the actual containing block of any grid item.
During grid's layout logic these override sizes are set according
to the CSS style rules. This affects how the grid container and its
children are going to be sized during layout. Grid Tracks sizing
algorithm depend on these override sizes.
In order to ensure that the tracks sizing algorithm produces the
same results when it's run consecutively several times, we need to
clear these override sizes and performs a layout of the affected grid
items. Otherwise, the affected items will return sizing values which
depend on the override values set in the previous layout, which in
some cases, like orthogonal flows, may change through different runs
of the sizing algorithm.
BUG=628565
Review-Url: https://codereview.chromium.org/2361373002
Cr-Commit-Position: refs/heads/master@{#424250}
4 files changed
