Display the site scheme, not the current scheme on Edit Site screen in network admin.

props johnbillion.
fixes #28406.

git-svn-id: https://develop.svn.wordpress.org/trunk@28643 602fd350-edb4-49c9-b593-d223f7449a82
Avoid stomping of the $plugin variable in activate_plugin().

fixes #28102.

git-svn-id: https://develop.svn.wordpress.org/trunk@28644 602fd350-edb4-49c9-b593-d223f7449a82