Add metadata-based duration retrieval

src/adts/adts-demuxer.ts

@@ -143,6 +143,10 @@ export class AdtsDemuxer extends Demuxer {
 		this.lastLoadedPos = header.startPos + header.frameLength;
 	}
 
+	async getDurationFromMetadata(): Promise<number | null> {
+		return null; // No way
+	}
+
 	async getMimeType() {
 		return 'audio/aac';
 	}
@@ -227,6 +231,10 @@ class AdtsAudioTrackBacking implements InputAudioTrackBacking {
 		return null;
 	}
 
+	async getDurationFromMetadata() {
+		return null;
+	}
+
 	async getLiveRefreshInterval() {
 		return null;
 	}