Use DataSpec.position except for specific use cases where the absolute position
within the resource is required within a DataSource chain. Where the absolute
position is required, use uriPositionOffset + position.
Pass the ads response as a data URI when setting media item playback properties
(if using the media item API) or as a DataSpec when constructing the AdsMediaSource (if using media sources directly). Util.getDataUriForString(String, String) can be used to construct a data URI from
literal string ads response (with MIME type text/xml).
Pass the ad tag URI when setting media item playback properties (if using the
media item API) or as a DataSpec when constructing the AdsMediaSource (if
using media sources directly).
Use ImaAdsLoader.requestAds(DataSpec, ViewGroup), specifying the ad tag data spec to
request, and migrate off deprecated builder methods/constructor that require an ad tag or
ads response.
Use ImaAdsLoader.Builder to create an instance. Pass the ad tag URI when setting media
item playback properties (if using the media item API) or as a DataSpec when
constructing the AdsMediaSource (if using media sources directly).