[css-grid] Use child's marginLogicalWidth to compute content-sized track

When computing min-content and max-content of the content-sized tracks
we are using the marginIntrinsicLogicalWidthForChild function, which
uses the grid's writing-mode to determine wether to use the child's
margin width or height. This is not correct when the grid item is
orthogonal.

This patch changes how we compute the tracks width so we use always
the item's marginLogicalWidth, which depends only on its own writing
mode.

BUG=670642

Review-Url: https://codereview.chromium.org/2543193002
Cr-Commit-Position: refs/heads/master@{#436149}
2 files changed