refactor(search): De-couple baloo URL parsing logic from UI
Summary:
Extracts the logic that parses baloosearch: urls into a new model class. The parser logic itself is kept as is.
The search box UI is later updated using the model fields.
This refactor has been proposed by @bruns in the review of D24422, as it largely simplifies the unit tests and further expansion/improvements.
Test Plan:
No behavior changes.
Test case is added in the follow-up revision: D25258
Reviewers: Dolphin, elvisangelaccio, bruns
Reviewed By: Dolphin, elvisangelaccio, bruns
Subscribers: ngraham, bruns, kfm-devel
Tags: Dolphin
Differential Revision: https://phabricator.kde.org/D25257