pgsql: Add numeric_int8_opt_error() to optionally suppress errors

Add numeric_int8_opt_error() to optionally suppress errors

This matches the existing numeric_int4_opt_error() (see commit
16d489b0fe).  It will be used by a future JSON-related patch, which
wants to report errors in its own way and thus does not want the
internal functions to throw any error.

Author: Jeevan Chalke <jeevan.chalke@enterprisedb.com>
Discussion:
https://www.postgresql.org/message-id/flat/CAM2+6=XjTyqrrqHAOj80r0wVQxJSxc0iyib9bPC55uFO9VKatg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c1b9e1e56d8c11a00869766a02de537d349586cd

Modified Files
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src/backend/utils/adt/numeric.c | 59 ++++++++++++++++++++++++++++++-----------
src/include/utils/numeric.h     |  1 +
2 files changed, 44 insertions(+), 16 deletions(-)