[PlasmaCore.IconItem] Regression: fix crash on source change
Summary:
When SvgSource is changed, old one is deleted. Connections are not automatically disconnected.
This change disconnects connections and fixes regression introduced in D28470.
BUG: 420801
FIXED-IN: 5.70
Test Plan:
STEPS TO REPRODUCE
- click on mute button for a device
- click on the desktop to collapse the applet
OBSERVED RESULT
crash in step 1 and in the rare case it doesn't crash it crash in step 2
EXPECTED RESULT
don't crash
Reviewers: Plasma, Frameworks, ngraham, davidedmundson
Reviewed By: ngraham
Subscribers: kde-frameworks-devel
Tags: Frameworks
Differential Revision: https://phabricator.kde.org/D29314