Register binder-depth per remote animation

Was just clearing all registered remotes. However, not all
remotes are from the same process, so things can get messed-up
(since we aren't relaunching the non-crashed binders, they won't
re-register). This is useful both for robustness as well as
making that failing tests don't break all subsequent tests.

This makes a death recipient for each remote.

Bug: 183993924
Test: crash launcher, make sure remote keyguard transition still
      works.
Change-Id: Idbec7ff72afd9bac974e7dbb1a067ad237606bd7