current buffer, and the invisible property has a `stickiness' such that
inserting a character at position POS would inherit the property it,
return POS + ADJ, otherwise return POS. If TEST_INTANG is non-zero,
- then intangibility is required as well as invisibleness.
+ then intangibility is required as well as invisibility.
TEST_OFFS should be either 0 or -1, and ADJ should be either 1 or -1.