Should be set to a constant specifying the SharedObject type identifier on the prototype of final derived owner classes. It is not used on counterpart (non-owner) classes.
sourceQueueLevel must be greater than the sourceQueueLevel of any ChunkSource whose download method depends on chunks from this source. A normal ChunkSource with no other dependencies should have a level of 0.
Begin downloading the specified the chunk. The returned promise should resolve when the downloaded data has been successfully decoded and stored in the chunk, or rejected if the download or decoding fails.
Note: This method must be defined by subclasses.
Chunk to download.
If this token is canceled, the download/decoding should be aborted if possible.
TODO(jbms): Move this back to the class definition above and declare this abstract once mixins are compatible with abstract classes.
Precondition: priorityTier <= ChunkPriorityTier.LAST_ORDERED_TIER
Protected ownerProtected refOptional options: boolean | AddEventListenerOptionsGenerated using TypeDoc
Base class inherited by both ChunkSource, for implementing the backend part of chunk sources that also have a frontend-part, as well as other chunk sources, such as the GenericFileSource, that has only a backend part.