Get in sync with rest of Plasma, also use same var names

Summary:
During D12656, it was suggested that it would be better to migrate to
ecm_qt_declare_logging_category.

Test Plan: It builds

Reviewers: #plasma, ivan, lbeltrame, davidedmundson

Reviewed By: #plasma, davidedmundson

Subscribers: plasma-devel

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D12658

Summary: Please check the rewrite of the method that was going QString -> QUrl -> QString -> QUrl.

Test Plan: none

Reviewers: ivan

Reviewed By: ivan

Subscribers: #plasma

Differential Revision: https://phabricator.kde.org/D1978

This reverts commit 535b348a.

This reverts commit 989ac229.

Summary:
...by adding the NO_POLICY_SCOPE flag as recommended by ECM's
documentation.

Reviewers: #plasma

Differential Revision: https://phabricator.kde.org/D1904

KActivities framework does not need i18n, so we can continue using
kactivities5 as the translation domain in the daemon.

spotted on http://ci-logs.kde.flaska.net/matrix.html
because it was the only one not red with Qt 5.2 :-)