Make AudioCapabilities constructor public

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=207707035

library/core/src/main/java/com/google/android/exoplayer2/audio/AudioCapabilities.java

@@ -25,9 +25,7 @@ import android.media.AudioManager;
 import android.support.annotation.Nullable;
 import android.support.annotation.Nullable;
 import java.util.Arrays;
 import java.util.Arrays;
 
 
-/**
- * Represents the set of audio formats that a device is capable of playing.
- */
+/** Represents the set of audio formats that a device is capable of playing. */
 @TargetApi(21)
 @TargetApi(21)
 public final class AudioCapabilities {
 public final class AudioCapabilities {
 
 
@@ -65,11 +63,15 @@ public final class AudioCapabilities {
    * Constructs new audio capabilities based on a set of supported encodings and a maximum channel
    * Constructs new audio capabilities based on a set of supported encodings and a maximum channel
    * count.
    * count.
    *
    *
+   * <p>Applications should generally call {@link #getCapabilities(Context)} to obtain an instance
+   * based on the capabilities advertised by the platform, rather than calling this constructor.
+   *
    * @param supportedEncodings Supported audio encodings from {@link android.media.AudioFormat}'s
    * @param supportedEncodings Supported audio encodings from {@link android.media.AudioFormat}'s
-   *     {@code ENCODING_*} constants.
+   *     {@code ENCODING_*} constants. Passing {@code null} indicates that no encodings are
+   *     supported.
    * @param maxChannelCount The maximum number of audio channels that can be played simultaneously.
    * @param maxChannelCount The maximum number of audio channels that can be played simultaneously.
    */
    */
-  /* package */ AudioCapabilities(int[] supportedEncodings, int maxChannelCount) {
+  public AudioCapabilities(@Nullable int[] supportedEncodings, int maxChannelCount) {
     if (supportedEncodings != null) {
     if (supportedEncodings != null) {
       this.supportedEncodings = Arrays.copyOf(supportedEncodings, supportedEncodings.length);
       this.supportedEncodings = Arrays.copyOf(supportedEncodings, supportedEncodings.length);
       Arrays.sort(this.supportedEncodings);
       Arrays.sort(this.supportedEncodings);