By and by Pooh and Piglet came along. Pooh was telling Piglet in a singing voice that it didn't seem to matter, if he didn't get any fatter, and he didn't think he was getting any fatter, what he did; and Piglet was wondering how long it would be before his haycorn came up.
This is from "The House At Pooh Corner". I couldn't grasp the structure of this sentence, so I asked it to native English speakers. A person said "what he did" is an older British phrase that roughly means "this is what he did". Another person said that "it didn't seem to matter, {if he didn't get any fatter, and he didn't think he was getting any fatter,} what he did". Which is correct? Thanks in advance.