Introduce common base class for system modal dialogs
This frees parts that don't care from layer-surface details making things more self contained and easier to test. Helps !700 (merged) too.
TODO:
-
add unit test for PhoshSystemModal -
unify CSS
I plan to move more stuff over so we can have consistent gestures etc out of the box but this is sufficient for #300 (closed) and other upcoming stuff.
Closes: #300 (closed)
Edited by Guido Gunther