Fix some nullness annotation warnings

PiperOrigin-RevId: 322780990

library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloader.java

@@ -43,7 +43,6 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
-import org.checkerframework.checker.nullness.compatqual.NullableType;
 
 /**
  * Base class for multi segment stream downloaders.
@@ -456,14 +455,14 @@ public abstract class SegmentDownloader<M extends FilterableManifest<M>> impleme
 
     public final Segment segment;
     public final CacheDataSource dataSource;
-    @NullableType private final ProgressNotifier progressNotifier;
+    @Nullable private final ProgressNotifier progressNotifier;
     public final byte[] temporaryBuffer;
     private final CacheWriter cacheWriter;
 
     public SegmentDownloadRunnable(
         Segment segment,
         CacheDataSource dataSource,
-        @NullableType ProgressNotifier progressNotifier,
+        @Nullable ProgressNotifier progressNotifier,
         byte[] temporaryBuffer) {
       this.segment = segment;
       this.dataSource = dataSource;

library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultAllocator.java

@@ -36,7 +36,7 @@ public final class DefaultAllocator implements Allocator {
   private int targetBufferSize;
   private int allocatedCount;
   private int availableCount;
-  @NullableType private Allocation[] availableAllocations;
+  private @NullableType Allocation[] availableAllocations;
 
   /**
    * Constructs an instance without creating any {@link Allocation}s up front.