Thanks to John's detective work, we now have an address. Cross checking the date of death with the probate calendars leads us to a reference to a will of a Henry JOHNSON of 9 Albion Road, Lewisham, who died on 9 November 1936. Probate was granted to "Mabel Florence, married woman". Does this name ring any bells?
There seems little doubt that this is your Henry. The probate calendars also show a will for Emily Charlotte JOHNSON at the same address who died in June 1921. In this case, probate was granted to Edward James STENT and Lucretia STENT.
Hope this helps