[MCPE-110361] PBR textures do not work when using texture variations

In a texture pack if you define a texture set for a block and that texture set contains a normal and MER file as documented in the RTX guide from NVIDA, the texture set works properly.

If you define a variation set for a block in the terrain_textures.json as below

{
 {
   "num_mip_levels" : 0,
   "padding" : 0,
   "resource_pack_name" : "vanilla",
   "texture_data" : {
      "dirt" : {
         "textures" : { "variations" : [
                           {"path" : "textures/blocks/dirt/0"},
                           {"path" : "textures/blocks/dirt/1"},
                           {"path" : "textures/blocks/dirt/2"},
                           {"path" : "textures/blocks/dirt/3"},
                           {"path" : "textures/blocks/dirt/4"},
                           {"path" : "textures/blocks/dirt/5"},
                           {"path" : "textures/blocks/dirt/6"} ]  }
      } 
  },
 "texture_name" : "atlas.terrain"
}

If the numbered files are texture sets, no MER or normal layer will be loaded, however the color layer is properly loaded.

I would expect that if the color layer is loaded, then the MER and Normal layer would be loaded.

I cannot find any documentation that states differently, i am happy to be proven wrong...