Similar to1a6d0ec71cwhich changed the mesh boolean node (and also caused this bug), this commit changes the material mapping for the exact mode of the boolean modifier. Now the result should contain any material on the faces of the input objects (including materials linked to objects and meshes). The improvement is possible because materials can be changed during evaluation (as of1a81d268a1). Differential Revision: https://developer.blender.org/D15365