More Desktop Icon fixes
Positioner: Load the positions at positioner completion
When positioner is loaded and the component is completed, we should ask the positioner our initial icon positions.
This fixes issues where icons are not in right position desktop-folderview is changed to desktop and back to folderview again
Positioner: Do not save 0x0 resolution
There is no reason for us to save positions for 0x0 resolution, so just ignore it.
This also avoids us trying to load for positions when there is no screen.
DesktopContainment: Check for screenUiReady before setting folderViewLayer active
We should set folderViewLayer active only when the screenUi is ready.
If we activate before it's ready, we end up in state where the icon grid is constantly being resized and reloaded. This causes glitchy look with the desktop icons jumping around, and makes the system more robust in general, avoiding any accidental icon moves if the grid suddenly becomes too small.
Instead, we now wait for things to be ready and have a correct resolution for the desktop icons grid, before doing anything.