Revert "[block-in-inline] Change the runtime flag to stable"

This reverts commit 4a76c96d2a4021257e691058c1fe1fb60d9d8327.

Reason for revert: crbug.com/1306628

The plan is to disable in M100 but enable in M101. To do
this, disable at trunk, then merge it to M100 and re-enable
only in trunk.

`WallpaperSubpageBrowserTest.LoadsCollectionsGrid` was
temporarily disabled as it relies on LayoutNGBlockInInline
(see `offsetHeight` in the "Known Behavior Changes" section of
the design doc.)

Original change's description:
> [block-in-inline] Change the runtime flag to stable
>
> Includes rebaselines of known changes that were not enabled
> when the flag was changed to "test" in r961524
> crrev.com/c/2956771. Please see the "Known Behavior Changes"
> section of the design doc:
> https://docs.google.com/document/d/15kgdIHhb9EVNup6Ir5NWwJxpzY5GH0ED7Ld3iMW3HlA/edit?pli=1#bookmark=id.a9j03i2hzxxf
>
> Bug: 716930
> Change-Id: Ic8d9134c592ebb8e88efc16aa636aed32a975ffc
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3398315
> Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
> Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
> Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
> Commit-Queue: Koji Ishii <kojii@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#967823}

Bug: 1306628, 716930
Change-Id: I7a87831361c5bac6f23b609ef29a4ab0b1345806
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3526799
Reviewed-by: Kent Tamura <tkent@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Reviewed-by: Jeffrey Young <cowmoo@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/main@{#981678}