Document the `let this = self;` idiom used in MIR building #183262

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8 errors and 6 warnings

unexpected closing delimiter: `}`

this file contains an unclosed delimiter

unexpected `if` in the condition expression

unexpected closing delimiter: `}`

lifetimes cannot start with a number

this file contains an unclosed delimiter

missing type for `static` item

mismatched closing delimiter: `}`

unexpected `cfg` condition value: `foo-method`

unexpected `cfg` condition value: `server`

unexpected `cfg` condition value: `client`

unexpected `cfg` condition value: `appservice-api-s`

unexpected `cfg` condition value: `appservice-api-c`