SERVER-14024: validate update insert fields at the end
(cherry picked from commit a0bad0a3f1b6562cd39fe66774db6ee486064045)

Conflicts:
	jstests/core/update_setOnInsert.js
SERVER-13764 update system retrieves nscanned / nscannedObjects from runner
Merge remote-tracking branch 'upstream/v2.6' into v2.6