Fixing read from mUsersRedirectedToOwnerForMedia sparse array.

ag/21547694 introduced some fixes in ContentProvider for clone
profile. However, a new bug was also introduced due to incorrect
index calculation. This CL fixes the same.

Bug: 270350104
Test: atest AppCloningHostTest
Change-Id: Iea3cc4b40194d809a62457899d7c4e96021692d7