fdo#84380 Remove repeated mouse handling code

Change-Id: I93d42ad234c4be20a4af0a2d68246699c6653105
Reviewed-on: https://gerrit.libreoffice.org/12270
Reviewed-by: Samuel Mehrbrodt <s.mehrbrodt@gmail.com>
Tested-by: Samuel Mehrbrodt <s.mehrbrodt@gmail.com>