Refactor migrateGridIfNeeded to pass the grid states and make it easier for unit testing

No-op change

Bug: 325286145
Flag: NA
Test: compiling
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:c3ffd41ff0f150ea91ad2a324dd4613b7d0cd89f)
Merged-In: I703c08059b81e20111c17a142dc54335f18a5a87
Change-Id: I703c08059b81e20111c17a142dc54335f18a5a87