pgsql: Move jsonapi.c and jsonapi.h to src/common.

Move jsonapi.c and jsonapi.h to src/common.

To make this work, (1) makeJsonLexContextCstringLen now takes the
encoding to be used as an argument; (2) check_stack_depth() is made to
do nothing in frontend code, and (3) elog(ERROR, ...) is changed to
pg_log_fatal + exit in frontend code.

Mark Dilger, reviewed and slightly revised by me.

Discussion: http://postgr.es/m/CA+TgmoYfOXhd27MUDGioVh6QtpD0C1K-f6ObSA10AWiHBAL5bA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/beb4699091e9fab1c5f465056bef35c9ddf7f9fc

Modified Files
--------------
contrib/hstore/hstore_io.c | 2 +-
src/backend/tsearch/to_tsany.c | 2 +-
src/backend/tsearch/wparser.c | 2 +-
src/backend/utils/adt/Makefile | 1 -
src/backend/utils/adt/json.c | 2 +-
src/backend/utils/adt/jsonb.c | 2 +-
src/backend/utils/adt/jsonb_util.c | 2 +-
src/backend/utils/adt/jsonfuncs.c | 7 +++---
src/common/Makefile | 1 +
src/{backend/utils/adt => common}/jsonapi.c | 36 +++++++++++++++++++++--------
src/include/{utils => common}/jsonapi.h | 2 ++
src/include/utils/jsonfuncs.h | 2 +-
12 files changed, 41 insertions(+), 20 deletions(-)