Adjust previews in a row to align with each other and remove whitespace.

- Introduces a WidgetTableRow that identifies preview height for all of
its children while keeping them aligned with minimum whitespace
- The fullSheet's move / change animations can conflict with the resize
so, we wait for them before performing resize of the row.

Bug: 335715046
Test: Manual
Flag: NONE BUGFIX
Change-Id: Id843430c7adfc228c219ba54d504baddba792df0