Allow partially valid results returned from `find` command when listing files and directories (#2311)
Allow partially valid results returned from `find` command when listing files and directories (#2311)

* Minor fix for the temporary directory for on-disk cache

If and only if the $TMPDIR env is not set should we try to fallback to
/tmp as the temporary directory for on-disk cache files.

* Do not return nil if `find` returns error when listing dir/files on remote ssh device

`find` command may partially succeed, in which case we should process
the successfully listed items and ignore the error messages. This CL
redirect the errors generated by `find` to /dev/null to strip away error
messages.

Qining/gapid,pmuetschard/gapid,google/agi,google/agi,Qining/gapid,google/agi,google/agi,pmuetschard/gapid,google/gapid,pmuetschard/gapid,Qining/gapid,google/gapid,google/gapid,google/gapid,google/agi,google/agi,Qining/gapid,pmuetschard/gapid,pmuetschard/gapid,pmuetschard/gapid,pmuetschard/gapid,google/agi,pmuetschard/gapid,google/gapid,Qining/gapid,google/gapid,Qining/gapid,google/gapid,Qining/gapid,Qining/gapid,google/gapid,google/agi