[ios, MagicStack] Modify Parcel Tracking and Tab Resumption Sequencing

- When receiving currently tracked parcels, MagicStackRankingModel
only has to indicate to the consumer to update the module order if
the rank has been fetched (and therefore the consumer has an initial
state)
- MagicStackRankingModel is not disconnected and dealloced in -stop
- TabResumptionMediator should skip calling
-tabResumptionHelperDidReplaceItem: if
IsIOSMagicStackCollectionViewEnabled() is not true to mirror how it
was done before IsIOSMagicStackCollectionView feature was introduced.
- Delay fetching parcels from ShoppingService until
ParcelTrackingMediator's delegate is set.

Bug: 336736962
Change-Id: Ibe75b2e0cac4444cc0d977c316308d6bc45f96b7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5527355
Reviewed-by: Scott Yoder <scottyoder@google.com>
Commit-Queue: Chris Lu <thegreenfrog@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1298865}