Remove SampleDataReader.skip

In order to make DataSource extend SampleDataReader.

PiperOrigin-RevId: 297368181

library/extractor/src/main/java/com/google/android/exoplayer2/extractor/DummyTrackOutput.java

@@ -27,6 +27,15 @@ import java.io.IOException;
  */
 public final class DummyTrackOutput implements TrackOutput {
 
+  // Even though read data is discarded, data source implementations could be making use of the
+  // buffer contents. For example, caches. So we cannot use a static field for this which could be
+  // shared between different threads.
+  private final byte[] readBuffer;
+
+  public DummyTrackOutput() {
+    readBuffer = new byte[4096];
+  }
+
   @Override
   public void format(Format format) {
     // Do nothing.
@@ -35,7 +44,8 @@ public final class DummyTrackOutput implements TrackOutput {
   @Override
   public int sampleData(SampleDataReader input, int length, boolean allowEndOfInput)
       throws IOException, InterruptedException {
-    int bytesSkipped = input.skip(length);
+    int bytesToSkipByReading = Math.min(readBuffer.length, length);
+    int bytesSkipped = input.read(readBuffer, /* offset= */ 0, bytesToSkipByReading);
     if (bytesSkipped == C.RESULT_END_OF_INPUT) {
       if (allowEndOfInput) {
         return C.RESULT_END_OF_INPUT;

library/extractor/src/main/java/com/google/android/exoplayer2/extractor/SampleDataReader.java

@@ -33,16 +33,4 @@ public interface SampleDataReader {
    * @throws InterruptedException If the thread has been interrupted.
    */
   int read(byte[] target, int offset, int length) throws IOException, InterruptedException;
-
-  /**
-   * Like {@link #read(byte[], int, int)}, except the sample data is skipped instead of read.
-   *
-   * @param length The maximum number of bytes to skip from the input.
-   * @return The number of bytes skipped, or {@link C#RESULT_END_OF_INPUT} if the input has ended.
-   *     This may be less than {@code length} because the end of the input (or available data) was
-   *     reached, the method was interrupted, or the operation was aborted early for another reason.
-   * @throws IOException If an error occurs reading from the input.
-   * @throws InterruptedException If the thread has been interrupted.
-   */
-  int skip(int length) throws IOException, InterruptedException;
 }