Fix Timeline.toBundle for empty timeline

PiperOrigin-RevId: 364513299

library/common/src/main/java/com/google/android/exoplayer2/Timeline.java

@@ -1291,7 +1291,9 @@ public abstract class Timeline implements Bundleable {
     }
 
     int[] shuffledWindowIndices = new int[windowCount];
-    shuffledWindowIndices[0] = getFirstWindowIndex(/* shuffleModeEnabled= */ true);
+    if (windowCount > 0) {
+      shuffledWindowIndices[0] = getFirstWindowIndex(/* shuffleModeEnabled= */ true);
+    }
     for (int i = 1; i < windowCount; i++) {
       shuffledWindowIndices[i] =
           getNextWindowIndex(

library/common/src/test/java/com/google/android/exoplayer2/TimelineTest.java

@@ -279,6 +279,11 @@ public class TimelineTest {
   }
 
   @Test
+  public void roundtripViaBundle_ofEmptyTimeline_returnsEmptyTimeline() {
+    TimelineAsserts.assertEmpty(Timeline.CREATOR.fromBundle(Timeline.EMPTY.toBundle()));
+  }
+
+  @Test
   public void roundtripViaBundle_ofWindow_yieldsEqualInstanceExceptUidAndManifest() {
     Timeline.Window window = new Timeline.Window();
     window.uid = new Object();