Add MediaCodecSelector.getPassthroughDecoderInfo.

Issue: #1518
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=122080068

library/src/main/java/com/google/android/exoplayer/MediaCodecUtil.java

@@ -99,7 +99,8 @@ public final class MediaCodecUtil {
    * @param mimeType The mime type.
    * @param secure Whether the decoder is required to support secure decryption. Always pass false
    *     unless secure decryption really is required.
-   * @return A list of all @{link DecoderInfo}s for the given mime type,
+   * @return A list of all @{link DecoderInfo}s for the given mime type, in the order given by
+   *     {@link MediaCodecList}.
    */
   public static synchronized List<DecoderInfo> getDecoderInfos(String mimeType, boolean secure)
       throws DecoderQueryException {