examples/Leaflet.PolarMap/projection-detection/demo.js
function(projection) {
  for (var key in projectedTiles) {
    if (projectedTiles.hasOwnProperty(key)) {
      if (key.indexOf(projection) !== -1) {
        return projectedTiles[key];
      }
    }
  }

  return null;
}
function(projection) {
  for (var key in projectedTiles) {
    if (projectedTiles.hasOwnProperty(key)) {
      if (key.indexOf(projection) !== -1) {
        return projectedTiles[key];
      }
    }
  }

  return null;
}
Return the tile layer that has a key containing `projection`