Auto merge of rust-lang#105436 - nnethercote:inline-place_contents_dr…

…op_state_cannot_differ, r=spastorino

Inline and remove `place_contents_drop_state_cannot_differ`.

It has a single call site and is hot enough to be worth inlining. And make sure `is_terminal_path` is inlined, too.

r? `@ghost`