Reduce code duplication for processing input events

Summary:
For every input event we have similar code. We go through all
InputFilters, invoke a method with some arguments and check whether
the filter returns true.

Instead of duplicating that logic everywhere, there is now one method
in InputRedirection which takes a std::function to call on the input
filters. The std::function is supposed to be generated with a std::bind
on the InputFilter::method with all the required arguments.

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D3806