Merge "jansson: Upgrade to 2.12."

third-party/jansson/jansson-2.11.tar.bz2.md5

third-party/jansson/jansson-2.12.tar.bz2.md5

third-party/jansson/patches/0001-Improve-test-coverage.patch

...ansson/patches/0017-Fix-error-handling-in-json_pack.patch

...patches/0022-Avoid-invalid-memory-read-in-json_pack.patch

...hes/0025-Call-va_end-after-va_copy-in-json_vsprintf.patch

...es/0027-Rename-a-varialble-that-shadows-another-one.patch

...0029-json_pack-Improve-handling-of-formats-with-and.patch

...patches/0030-More-work-on-json_pack-error-reporting.patch

...emove-inappropriate-jsonp_free-which-caused-segment.patch

third-party/jansson/patches/README

third-party/versions.mak