Remove TrackGroup.adaptive flag.

It's only "needed" for HLS, and this requirement will
go away soon. It's safe to remove the flag ahead of
this because a TrackSelector can/should not attempt to
adapt between multiple audio/text tracks.

Also remove unnecessary restrictions on TrackGroups
being non-empty and only of known types.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=128376601

demo/src/main/java/com/google/android/exoplayer2/demo/TrackSelectionHelper.java

@@ -123,7 +123,7 @@ import java.util.Locale;
       TrackGroup group = trackGroups.get(groupIndex);
       trackViews[groupIndex] = new CheckedTextView[group.length];
       for (int trackIndex = 0; trackIndex < group.length; trackIndex++) {
-        if (trackIndex == 0 || !group.adaptive) {
+        if (trackIndex == 0) {
           root.addView(inflater.inflate(R.layout.list_divider, root, false));
         }
         int trackViewLayoutId = group.length < 2 || !trackGroupsAdaptive[groupIndex]

library/src/main/java/com/google/android/exoplayer2/source/TrackGroup.java

@@ -20,24 +20,21 @@ import com.google.android.exoplayer2.util.Assertions;
 
 import java.util.Arrays;
 
+// TODO: Add an allowMultipleStreams boolean to indicate where the one stream per group restriction
+// does not apply.
 /**
  * Defines a group of tracks exposed by a {@link MediaPeriod}.
  * <p>
  * A {@link MediaPeriod} is only able to provide one {@link SampleStream} corresponding to a group
- * at any given time. If {@link #adaptive} is true this {@link SampleStream} can adapt between
- * multiple tracks within the group. If {@link #adaptive} is false then it's only possible to
- * consume one track from the group at a given time.
+ * at any given time, however this {@link SampleStream} may adapt between multiple tracks within the
+ * group.
  */
 public final class TrackGroup {
 
   /**
-   * The number of tracks in the group. Always greater than zero.
+   * The number of tracks in the group.
    */
   public final int length;
-  /**
-   * Whether it's possible to adapt between multiple tracks in the group.
-   */
-  public final boolean adaptive;
 
   private final Format[] formats;
 
@@ -45,19 +42,10 @@ public final class TrackGroup {
   private int hashCode;
 
   /**
-   * @param format The format of the single track.
-   */
-  public TrackGroup(Format format) {
-    this(false, Assertions.checkNotNull(format));
-  }
-
-  /**
-   * @param adaptive Whether it's possible to adapt between multiple tracks in the group.
-   * @param formats The track formats. Must not be null or empty. Must not contain null elements.
+   * @param formats The track formats. Must not be null or contain null elements.
    */
-  public TrackGroup(boolean adaptive, Format... formats) {
+  public TrackGroup(Format... formats) {
     Assertions.checkState(formats.length > 0);
-    this.adaptive = adaptive;
     this.formats = formats;
     this.length = formats.length;
   }
@@ -91,7 +79,6 @@ public final class TrackGroup {
   public int hashCode() {
     if (hashCode == 0) {
       int result = 17;
-      result = 31 * result + (adaptive ? 1231 : 1237);
       result = 31 * result + Arrays.hashCode(formats);
       hashCode = result;
     }
@@ -107,8 +94,7 @@ public final class TrackGroup {
       return false;
     }
     TrackGroup other = (TrackGroup) obj;
-    return adaptive == other.adaptive && length == other.length
-        && Arrays.equals(formats, other.formats);
+    return length == other.length && Arrays.equals(formats, other.formats);
   }
 
 }

library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaPeriod.java

@@ -33,10 +33,7 @@ import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.upstream.Allocator;
 import com.google.android.exoplayer2.upstream.Loader;
 
-import android.util.Pair;
-
 import java.io.IOException;
-import java.util.Arrays;
 import java.util.List;
 
 /**
@@ -52,7 +49,6 @@ import java.util.List;
   private final Loader loader;
   private final long durationUs;
   private final TrackGroupArray trackGroups;
-  private final int[] trackGroupAdaptationSetIndices;
 
   private ChunkSampleStream<DashChunkSource>[] sampleStreams;
   private CompositeSequenceableLoader sequenceableLoader;
@@ -74,9 +70,7 @@ import java.util.List;
     this.loader = loader;
     durationUs = manifest.dynamic ? C.UNSET_TIME_US : manifest.getPeriodDuration(index) * 1000;
     period = manifest.getPeriod(index);
-    Pair<TrackGroupArray, int[]> trackGroupsAndAdaptationSetIndices = buildTrackGroups(period);
-    trackGroups = trackGroupsAndAdaptationSetIndices.first;
-    trackGroupAdaptationSetIndices = trackGroupsAndAdaptationSetIndices.second;
+    trackGroups = buildTrackGroups(period);
   }
 
   public void updateManifest(DashManifest manifest, int index) {
@@ -206,37 +200,23 @@ import java.util.List;
 
   // Internal methods.
 
-  private static Pair<TrackGroupArray, int[]> buildTrackGroups(Period period) {
-    int trackGroupCount = 0;
-    int[] trackGroupAdaptationSetIndices = new int[period.adaptationSets.size()];
+  private static TrackGroupArray buildTrackGroups(Period period) {
     TrackGroup[] trackGroupArray = new TrackGroup[period.adaptationSets.size()];
     for (int i = 0; i < period.adaptationSets.size(); i++) {
       AdaptationSet adaptationSet = period.adaptationSets.get(i);
-      int adaptationSetType = adaptationSet.type;
       List<Representation> representations = adaptationSet.representations;
-      if (!representations.isEmpty() && (adaptationSetType == C.TRACK_TYPE_AUDIO
-          || adaptationSetType == C.TRACK_TYPE_VIDEO || adaptationSetType == C.TRACK_TYPE_TEXT)) {
-        Format[] formats = new Format[representations.size()];
-        for (int j = 0; j < formats.length; j++) {
-          formats[j] = representations.get(j).format;
-        }
-        trackGroupAdaptationSetIndices[trackGroupCount] = i;
-        boolean adaptive = adaptationSetType == C.TRACK_TYPE_VIDEO;
-        trackGroupArray[trackGroupCount++] = new TrackGroup(adaptive, formats);
+      Format[] formats = new Format[representations.size()];
+      for (int j = 0; j < formats.length; j++) {
+        formats[j] = representations.get(j).format;
       }
+      trackGroupArray[i] = new TrackGroup(formats);
     }
-    if (trackGroupCount < trackGroupArray.length) {
-      trackGroupAdaptationSetIndices = Arrays.copyOf(trackGroupAdaptationSetIndices,
-          trackGroupCount);
-      trackGroupArray = Arrays.copyOf(trackGroupArray, trackGroupCount);
-    }
-    TrackGroupArray trackGroups = new TrackGroupArray(trackGroupArray);
-    return Pair.create(trackGroups, trackGroupAdaptationSetIndices);
+    return new TrackGroupArray(trackGroupArray);
   }
 
   private ChunkSampleStream<DashChunkSource> buildSampleStream(TrackSelection selection,
       long positionUs) {
-    int adaptationSetIndex = trackGroupAdaptationSetIndices[trackGroups.indexOf(selection.group)];
+    int adaptationSetIndex = trackGroups.indexOf(selection.group);
     AdaptationSet adaptationSet = period.adaptationSets.get(adaptationSetIndex);
     DashChunkSource chunkSource = chunkSourceFactory.createDashChunkSource(loader, manifest, index,
         adaptationSetIndex, selection, elapsedRealtimeOffset);

library/src/main/java/com/google/android/exoplayer2/source/hls/HlsChunkSource.java

@@ -126,7 +126,7 @@ public class HlsChunkSource {
       variantFormats[i] = variants[i].format;
       initialTrackSelection[i] = i;
     }
-    trackGroup = new TrackGroup(formatEvaluator != null, variantFormats);
+    trackGroup = new TrackGroup(variantFormats);
     selectTracksInternal(new TrackSelection(trackGroup, initialTrackSelection), false);
   }
 

library/src/main/java/com/google/android/exoplayer2/source/hls/HlsSampleStreamWrapper.java

@@ -543,7 +543,7 @@ import java.util.List;
         for (int j = 0; j < chunkSourceTrackCount; j++) {
           formats[j] = getSampleFormat(chunkSourceTrackGroup.getFormat(j), sampleFormat);
         }
-        trackGroups[i] = new TrackGroup(chunkSourceTrackGroup.adaptive, formats);
+        trackGroups[i] = new TrackGroup(formats);
         primaryTrackGroupIndex = i;
       } else {
         Format trackFormat = null;

library/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaSource.java

@@ -49,7 +49,6 @@ import android.os.SystemClock;
 import android.util.Base64;
 
 import java.io.IOException;
-import java.util.Arrays;
 import java.util.List;
 
 /**
@@ -90,7 +89,6 @@ public final class SsMediaSource implements MediaPeriod, MediaSource,
   private long durationUs;
   private TrackEncryptionBox[] trackEncryptionBoxes;
   private TrackGroupArray trackGroups;
-  private int[] trackGroupElementIndices;
 
   public SsMediaSource(Uri manifestUri, DataSource.Factory manifestDataSourceFactory,
       SsChunkSource.Factory chunkSourceFactory, Handler eventHandler,
@@ -254,7 +252,6 @@ public final class SsMediaSource implements MediaPeriod, MediaSource,
     durationUs = 0;
     trackEncryptionBoxes = null;
     trackGroups = null;
-    trackGroupElementIndices = null;
   }
 
   // SequenceableLoader.Callback implementation
@@ -337,30 +334,18 @@ public final class SsMediaSource implements MediaPeriod, MediaSource,
   }
 
   private void buildTrackGroups(SsManifest manifest) {
-    int trackGroupCount = 0;
-    trackGroupElementIndices = new int[manifest.streamElements.length];
     TrackGroup[] trackGroupArray = new TrackGroup[manifest.streamElements.length];
     for (int i = 0; i < manifest.streamElements.length; i++) {
       StreamElement streamElement = manifest.streamElements[i];
-      int streamElementType = streamElement.type;
       Format[] formats = streamElement.formats;
-      if (formats.length > 0 && (streamElementType == C.TRACK_TYPE_AUDIO
-          || streamElementType == C.TRACK_TYPE_VIDEO || streamElementType == C.TRACK_TYPE_TEXT)) {
-        trackGroupElementIndices[trackGroupCount] = i;
-        boolean adaptive = streamElementType == C.TRACK_TYPE_VIDEO;
-        trackGroupArray[trackGroupCount++] = new TrackGroup(adaptive, formats);
-      }
-    }
-    if (trackGroupCount < trackGroupArray.length) {
-      trackGroupElementIndices = Arrays.copyOf(trackGroupElementIndices, trackGroupCount);
-      trackGroupArray = Arrays.copyOf(trackGroupArray, trackGroupCount);
+      trackGroupArray[i] = new TrackGroup(formats);
     }
     trackGroups = new TrackGroupArray(trackGroupArray);
   }
 
   private ChunkSampleStream<SsChunkSource> buildSampleStream(TrackSelection selection,
       long positionUs) {
-    int streamElementIndex = trackGroupElementIndices[trackGroups.indexOf(selection.group)];
+    int streamElementIndex = trackGroups.indexOf(selection.group);
     SsChunkSource chunkSource = chunkSourceFactory.createChunkSource(manifestLoader, manifest,
         streamElementIndex, selection, trackEncryptionBoxes);
     return new ChunkSampleStream<>(manifest.streamElements[streamElementIndex].type, chunkSource,

library/src/main/java/com/google/android/exoplayer2/trackselection/DefaultTrackSelector.java

@@ -208,10 +208,6 @@ public class DefaultTrackSelector extends MappingTrackSelector {
   private static int[] getAdaptiveTracksOfGroup(TrackGroup trackGroup, int[] formatSupport,
       boolean allowMixedMimeTypes, int requiredAdaptiveSupport, int maxVideoWidth,
       int maxVideoHeight) {
-    if (!trackGroup.adaptive) {
-      return NO_TRACKS;
-    }
-
     String mimeType = null;
     int adaptiveTracksCount = 0;
     if (allowMixedMimeTypes) {

library/src/main/java/com/google/android/exoplayer2/trackselection/MappingTrackSelector.java

@@ -560,10 +560,6 @@ public abstract class MappingTrackSelector extends TrackSelector {
      *     {@link RendererCapabilities#ADAPTIVE_NOT_SUPPORTED}.
      */
     public int getAdaptiveSupport(int rendererIndex, int groupIndex, int[] trackIndices) {
-      TrackGroup trackGroup = trackGroups[rendererIndex].get(groupIndex);
-      if (!trackGroup.adaptive) {
-        return RendererCapabilities.ADAPTIVE_NOT_SUPPORTED;
-      }
       int handledTrackCount = 0;
       int adaptiveSupport = RendererCapabilities.ADAPTIVE_SEAMLESS;
       boolean multipleMimeTypes = false;