message: Fix mapType for webMercator (off by 1). Correct groundBias extraction.
diff: @@ -211,7 +211,7 @@ class WebMercatorTileLoader extends TileLoader {
  }
  // The type of background map
  -enum MapType { Street = 0, Aerial = 1, Hybrid = 2 }
  +enum MapType { Street = 1, Aerial = 2, Hybrid = 3 } // These are aligned with BackgroundMapType in MicroStation.
  // Represents the service that is providing map tiles for Web Mercator models (background maps).
  abstract class ImageryProvider {
  @@ -601,7 +601,7 @@ export class BackgroundMapState {
  this._providerName = JsonUtils.asString(json.providerName, "BingProvider");
  // this.providerData = JsonUtils.asString(json.providerData, "aerial");
  this._groundBias = JsonUtils.asDouble(json.groundBias, 0.0);
  - this._mapType = JsonUtils.asInt(json.mapType, MapType.Hybrid);
  + this._mapType = json.providerData ? JsonUtils.asInt(json.providerData.mapType, MapType.Hybrid) : MapType.Hybrid;
  }
  private loadTileTree(): TileTree.LoadStatus {
  @@ -620,7 +620,7 @@ export class BackgroundMapState {
  if (this._provider === undefined)
  throw new BentleyError(IModelStatus.BadModel, "WebMercator provider invalid");
  - const loader = new WebMercatorTileLoader(this._provider, this._iModel, JsonUtils.asDouble(this._groundBias, 0.0));
  + const loader = new WebMercatorTileLoader(this._provider, this._iModel, this._groundBias);
  const tileTreeProps = new WebMercatorTileTreeProps(loader.mercatorToDb);
  this.setTileTree(tileTreeProps, loader);
  return this._loadStatus;
  