Merge branch 'js/fsmonitor-unpack-fix'

The data structure used by fsmonitor interface was not properly
duplicated during an in-core merge, leading to use-after-free etc.

* js/fsmonitor-unpack-fix:
  fsmonitor: do not forget to release the token in `discard_index()`
  fsmonitor: fix memory corruption in some corner cases

diff --cc read-cache.c
Simple merge

diff --cc unpack-trees.c
Simple merge