function clearSymbolLayer(layer) {
  // get existing overrides
  let existingOverrides = Layers.getSymbolOverrides(layer)
  if (!existingOverrides) return

  // clear overrides except for symbol overrides
  let clearedOverrides = clearOverrides(existingOverrides)

  // remove metadata
  removeLayerMetadata(layer)

  // set cleared overrides
  Layers.setSymbolOverrides(layer, clearedOverrides)
}
Clears the symbol layer.

@param {MSSymbolInstance} layer