Rust Binder cleanup is reworked to match the order in which C Binder
cleans up things. A few notes on the changes:
* Actually dropping thread objects is done at the very end because they
contain a call to synchronize_rcu() which is slow. This ensures that
death notifications are sent without waiting for those calls. This
avoids failures in rustBinderTest. (The test is already flaky, but
this extra sleep makes the flake much more likely to happen.)
* We now free refs on remote nodes in release explicitly. Previously
that only happened implicitly when everything keeping the ref alive
has been dropped. To avoid spurious warnings from this, the warning
print about dropping a ref that doesn't exist is only printed if the
process is alive.
Bug: 431914626
Change-Id: I3d1f4f15ffac7587d1bb0113a41330b2aea69b3d
Signed-off-by: Alice Ryhl <aliceryhl@google.com>