Summary:
Don't construct a QUrl for every source strings. Check it's a file url
first (which is the only kind of url we support at the moment)
When extracting the path, use toLocalFile, so it works on platforms where
path!=toLocalPath (e.g. windows)
Don't split a string and get a chunk, but just extract the chunk we need
with section. Reduces allocations that are automatically discarded.
Narrow iconPath scope
Test Plan: Tests still pass, plasmashell still works
Reviewers: #frameworks, #plasma, mart
Reviewed By: #plasma, mart
Subscribers: plasma-devel
Tags: #plasma, #frameworks
Differential Revision: https://phabricator.kde.org/D6014
3b303d7363