HLS: Fix issue where new init segment would not be loaded

Issue: #9004
#minor-release
PiperOrigin-RevId: 379516815

RELEASENOTES.md

@@ -58,6 +58,11 @@
         is set incorrectly
         ([#4083](https://github.com/google/ExoPlayer/issues/4083)). Such content
         is malformed and should be re-encoded.
+*   HLS:
+    *   Fix issue where a new initialization segment, as specified by an
+        `EXT-X-MAP` tag in a media playlist, would not be loaded when
+        encountered during playback
+        ([#9004](https://github.com/google/ExoPlayer/issues/9004)).
 *   Ad playback:
     *   Support changing ad break positions in the player logic
         ([#5067](https://github.com/google/ExoPlayer/issues/5067).

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaChunk.java

@@ -137,12 +137,19 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
     ParsableByteArray scratchId3Data;
 
     if (previousChunk != null) {
+      boolean isSameInitData =
+          initDataSpec == previousChunk.initDataSpec
+              || (initDataSpec != null
+                  && previousChunk.initDataSpec != null
+                  && initDataSpec.uri.equals(previousChunk.initDataSpec.uri)
+                  && initDataSpec.position == previousChunk.initDataSpec.position);
       boolean isFollowingChunk =
           playlistUrl.equals(previousChunk.playlistUrl) && previousChunk.loadCompleted;
       id3Decoder = previousChunk.id3Decoder;
       scratchId3Data = previousChunk.scratchId3Data;
       previousExtractor =
-          isFollowingChunk
+          isSameInitData
+                  && isFollowingChunk
                   && !previousChunk.extractorInvalidated
                   && previousChunk.discontinuitySequenceNumber == discontinuitySequenceNumber
               ? previousChunk.extractor