fix(HLS): Fix clear init segment mapping (#6000)

Author: avelad

lib/hls/hls_parser.js

@@ -295,6 +295,7 @@ shaka.hls.HlsParser = class {
     this.groupIdToStreamInfosMap_.clear();
     this.groupIdToCodecsMap_.clear();
     this.globalVariables_.clear();
+    this.mapTagToInitSegmentRefMap_.clear();
 
     if (this.contentSteeringManager_) {
       this.contentSteeringManager_.destroy();
@@ -905,6 +906,7 @@ shaka.hls.HlsParser = class {
     let initData = null;
     const initSegmentRef = this.getInitSegmentReference_(
         playlist, middleSegment.tags, getUris);
+    this.mapTagToInitSegmentRefMap_.clear();
     if (initSegmentRef) {
       const initSegmentRequest = shaka.net.NetworkingEngine.makeRequest(
           initSegmentRef.getUris(), this.config_.retryParameters);