pgsql: Better fix for "unarchived WAL files get deleted on crash recove

Better fix for "unarchived WAL files get deleted on crash recovery" bug.

Revert my earlier fix for the bug that unarchived WAL files get deleted on
crash recovery, commit c9cc7e05c6d82a9781883a016c70d95aa4923122. We create
a .done file for files streamed or restored from archive, so the WAL file
recycling logic used during normal operation works just as well during
archive recovery.

Per Fujii Masao's suggestion.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1bd42cd70abdbc946ad64c3c8eaefed4bb8b1145

Modified Files
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src/backend/access/transam/xlog.c |   30 +-----------------------------
1 files changed, 1 insertions(+), 29 deletions(-)