This patch allows dropping material assets from material slot under the mouse
cursor. Before this change the material slot had to be hand-picked from the
properties panel.
For consistency it is chosen to do this in any shading mode as the tooltip shows
what is exactly going to happen during release.
The feature also works for other object types than Meshes as it uses the drawn surface on the
GPU to detect the material slots.
{F10277324}
Selection particle hair material slot
{F10285709}
There seems to be an issue in certain scenes. Not able to reproduce in master, so need to check.
{F10277318}