This implements getvar all by invoking each callback and writing an INFO
status for each result. For commands that take arguments, the variable
handler can specify a function that returns all possible arguments.
Currently this only applies to partition variables.
Bug: 78793464
Test: fastboot getvar all works
Change-Id: I1cf84e06bf67614b6f56171c0ee6ca5d7ac383c9
When flashing logical partitions, we read the "super" partition metadata
corresponding to the current slot. We then temporarily create a
device-mapper device for that partition, and immediately destroy the
device after all operations are complete. We do not mount partitions
ahead of time, or keep them mounted, because a fastboot operation may
change the layout of the logical partition table (or change which slot
is current).
Bug: 78793464
Test: fastboot flash a logical partition under "super"
Change-Id: Id2a61d3592decabeebfd283c4fd6e6cbe576a18c
