ledflasher: Removing brillo::Any from weaved's public APIs

Weaved replaces brillo::Any with base::Value in its client library,
so need to update clients.

Also this removes last D-Bus dependencies from ledflasher.

Bug: 26558300
Change-Id: I8265e06aca6f707dde6edbebeafe0b28b8eb17ff
3 files changed