Layout: Convert GridTrackSizingAlgorithm to GarbageCollected

Convert GridTrackSizingAlgorithm and related classes to GCed to replace
UntracedMembers in them added by https://crrev.com/c/2465602 to Members.

This is a follow-up for https://crrev.com/c/2465602.

Bug: 1030176
Change-Id: I297904c67cfd4630940a384cff13b57ed6b704e6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2398749


Commit-Queue: Yuki Yamada <yukiy@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: Keishi Hattori <keishi@chromium.org>
Cr-Commit-Position: refs/heads/main@{#915899}