Fix T69895: X3D Import and Export returns error on meshes with vertex colors.

2.8x materials don't have any indication they should use vcols anymore,
that should be handled at node-based shader level now. For now just
ignore, and always export/import active vcols.

io_scene_x3d/__init__.py

@@ -21,7 +21,7 @@
 bl_info = {
     "name": "Web3D X3D/VRML2 format",
     "author": "Campbell Barton, Bart, Bastien Montagne, Seva Alekseyev",
-    "version": (2, 2, 4),
+    "version": (2, 2, 5),
     "blender": (2, 81, 6),
     "location": "File > Import-Export",
     "description": "Import-Export X3D, Import VRML2",

io_scene_x3d/export_x3d.py

@@ -583,7 +583,7 @@ def export(file,
             # Py dict are sorted now, so we can use directly polygons_groups.items()
             # and still get consistent reproducible outputs.
 
-            is_col = (mesh.vertex_colors.active and (material is None or material.use_vertex_color_paint))
+            is_col = mesh.vertex_colors.active
             mesh_loops_col = mesh.vertex_colors.active.data if is_col else None
 
             # Check if vertex colors can be exported in per-vertex mode.

io_scene_x3d/import_x3d.py

@@ -2717,7 +2717,7 @@ def appearance_CreateMaterial(vrmlname, mat, ancestry, is_vcol):
     bpymat.alpha = 1.0 - mat.getFieldAsFloat('transparency', 0.0, ancestry)
     if bpymat.alpha < 0.999:
         bpymat.use_transparency = True
-    if is_vcol:
+    if False and is_vcol:
         bpymat.use_vertex_color_paint = True
     return bpymat
 
@@ -2869,10 +2869,10 @@ def appearance_Create(vrmlname, material, tex_node, ancestry, node, is_vcol):
     if tex_node:  # Texture caching inside there
         bpyima = appearance_LoadTexture(tex_node, ancestry, node)
 
-    if 0 & is_vcol:
+    if False and is_vcol:
         bpymat.use_vertex_color_paint = True
 
-    if 0 and bpyima:
+    if False and bpyima:
         tex_has_alpha = bpyima.alpha_mode not in {'NONE', 'CHANNEL_PACKED'}
 
         texture = bpy.data.textures.new(bpyima.name, 'IMAGE')