Regression: devel docgen cannot generate document for method

[khchen]

Example

type
  Test* = ref object

proc test1*(self: Test) =
  ## Show this document

method test2*(self: Test) =
  ## This document disappeared

Current Output [HTML]

Procs
proc test1(self: Test) {...}
Show this document

Methods
method test2(self: Test) {...}

$ nim -v
Nim Compiler Version 1.3.5 [Windows: amd64]
Compiled at 2020-06-16