The 'set' command in the Python client interpretes None as the
string 'None.' If no password is set on the master, a detach/attach
(such as is done with promote) will have the slaves try and use 'none'
as a password. This will cause them to not be able to connect to the
master and leave them in a detached state.
The 'masterpass' is now set to an empty string if no password is set.
The restart of Redis was also moved before attaching the slave,
so that the mapped CONFIG command is recognized properly. This is
required so that setting the master password completes successfully.
(cherry picked from commit 6c4db5d327)
Closes-Bug: #1498208
Change-Id: Ibc842b95fd191908d4fac420030f84393c696013
Depends-On: Ida0aa155b1e1ec7b8e9fa73006d3db9a88ffea02
5bc4d89863