Fix WavExtractor bug.

When skipToData is called the peek position is not equal
to the read position of the input. Hence peeking a chunk
header and then skipping by that amount wont do the right
thing :)!
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=122157603

library/src/main/java/com/google/android/exoplayer/extractor/wav/WavHeaderReader.java

@@ -125,6 +125,9 @@ import java.io.IOException;
     Assertions.checkNotNull(input);
     Assertions.checkNotNull(wavHeader);
 
+    // Make sure the peek position is set to the read position before we peek the first header.
+    input.resetPeekPosition();
+
     ParsableByteArray scratch = new ParsableByteArray(ChunkHeader.SIZE_IN_BYTES);
     // Skip all chunks until we hit the data header.
     ChunkHeader chunkHeader = ChunkHeader.peek(input, scratch);