Merge branch 'master' into blender2.8

Conflicts:
	source/blender/blenkernel/BKE_material.h
	source/blender/blenkernel/BKE_mesh.h
	source/blender/blenkernel/intern/library_remap.c
	source/blender/blenkernel/intern/material.c
	source/blender/editors/object/object_relations.c
	source/blender/editors/render/render_preview.c
	source/blender/makesrna/intern/rna_object.c

source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp

@@ -838,7 +838,7 @@ void BlenderStrokeRenderer::GenerateStrokeMesh(StrokeGroup *group, bool hasTex)
 		material_index++;
 	} // loop over strokes
 
-	test_object_materials(object_mesh, (ID *)mesh);
+	test_object_materials(freestyle_bmain, object_mesh, (ID *)mesh);
 
 #if 0 // XXX
 	BLI_assert(mesh->totvert == vertex_index);