The class is generally useful, so it only makes sense in panel.js
for historical reasons. Because other parts of the code are
using it, though, problems are cropping up that require a
workaround like:
placeSpinner: function(...) {
/* This is here because of recursive imports */
const Panel = imports.ui.panel;
Panel.AnimatedIcon(spinnerIcon, WORK_SPINNER_ICON_SIZE);
...
}
This commit moves AnimatedIcon to its own file so we can drop that
workaround.
