Add reset() to SampleQueue. Deprecate reset(boolean) and disable()

The deprecated methods will be removed as soon as HLS is migrated
to use the new ones.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160827936

library/core/src/androidTest/java/com/google/android/exoplayer2/source/SampleQueueTest.java

@@ -93,10 +93,10 @@ public class SampleQueueTest extends TestCase {
     inputBuffer = null;
   }
 
-  public void testDisableReleasesAllocations() {
+  public void testResetReleasesAllocations() {
     writeTestData();
     assertAllocationCount(10);
-    sampleQueue.disable();
+    sampleQueue.reset();
     assertAllocationCount(0);
   }
 
@@ -545,8 +545,8 @@ public class SampleQueueTest extends TestCase {
   }
 
   /**
-   * Asserts {@link SampleQueue#readData} is behaving correctly, given there are no samples
+   * Asserts {@link SampleQueue#read} is behaving correctly, given there are no samples to read and
-   * to read and the last format to be written to the sample queue is {@code endFormat}.
+   * the last format to be written to the sample queue is {@code endFormat}.
    *
    * @param endFormat The last format to be written to the sample queue, or null of no format has
    *     been written.
@@ -573,7 +573,7 @@ public class SampleQueueTest extends TestCase {
   }
 
   /**
-   * Asserts {@link SampleQueue#readData} returns {@link C#RESULT_NOTHING_READ}.
+   * Asserts {@link SampleQueue#read} returns {@link C#RESULT_NOTHING_READ}.
    *
    * @param formatRequired The value of {@code formatRequired} passed to readData.
    */
@@ -589,7 +589,7 @@ public class SampleQueueTest extends TestCase {
   }
 
   /**
-   * Asserts {@link SampleQueue#readData} returns {@link C#RESULT_BUFFER_READ} and that the
+   * Asserts {@link SampleQueue#read} returns {@link C#RESULT_BUFFER_READ} and that the
    * {@link DecoderInputBuffer#isEndOfStream()} is set.
    *
    * @param formatRequired The value of {@code formatRequired} passed to readData.
@@ -608,8 +608,8 @@ public class SampleQueueTest extends TestCase {
   }
 
   /**
-   * Asserts {@link SampleQueue#readData} returns {@link C#RESULT_FORMAT_READ} and that the
+   * Asserts {@link SampleQueue#read} returns {@link C#RESULT_FORMAT_READ} and that the format
-   * format holder is filled with a {@link Format} that equals {@code format}.
+   * holder is filled with a {@link Format} that equals {@code format}.
    *
    * @param formatRequired The value of {@code formatRequired} passed to readData.
    * @param format The expected format.
@@ -626,8 +626,8 @@ public class SampleQueueTest extends TestCase {
   }
 
   /**
-   * Asserts {@link SampleQueue#readData} returns {@link C#RESULT_BUFFER_READ} and that the
+   * Asserts {@link SampleQueue#read} returns {@link C#RESULT_BUFFER_READ} and that the buffer is
-   * buffer is filled with the specified sample data.
+   * filled with the specified sample data.
    *
    * @param timeUs The expected buffer timestamp.
    * @param isKeyframe The expected keyframe flag.

library/core/src/main/java/com/google/android/exoplayer2/source/ExtractorMediaPeriod.java

@@ -150,8 +150,8 @@ import java.util.Arrays;
   public void release() {
     boolean releasedSynchronously = loader.release(this);
     if (prepared && !releasedSynchronously) {
-      // Discard as much as we can synchronously. We only do this if we're prepared, since
+      // Discard as much as we can synchronously. We only do this if we're prepared, since otherwise
-      // otherwise sampleQueues may still be being modified by the loading thread.
+      // sampleQueues may still be being modified by the loading thread.
       for (SampleQueue sampleQueue : sampleQueues) {
         sampleQueue.discardToEnd();
       }
@@ -164,7 +164,7 @@ import java.util.Arrays;
   public void onLoaderReleased() {
     extractorHolder.release();
     for (SampleQueue sampleQueue : sampleQueues) {
-      sampleQueue.reset(true);
+      sampleQueue.reset();
     }
   }
 
@@ -227,7 +227,15 @@ import java.util.Arrays;
     if (enabledTrackCount == 0) {
       notifyReset = false;
       if (loader.isLoading()) {
+        // Discard as much as we can synchronously.
+        for (SampleQueue sampleQueue : sampleQueues) {
+          sampleQueue.discardToEnd();
+        }
         loader.cancelLoading();
+      } else {
+        for (SampleQueue sampleQueue : sampleQueues) {
+          sampleQueue.reset();
+        }
       }
     } else if (seekRequired) {
       positionUs = seekToUs(positionUs);
@@ -327,7 +335,7 @@ import java.util.Arrays;
         loader.cancelLoading();
       } else {
         for (int i = 0; i < trackCount; i++) {
-          sampleQueues[i].reset(trackEnabledStates[i]);
+          sampleQueues[i].reset();
         }
       }
     }
@@ -388,7 +396,7 @@ import java.util.Arrays;
     }
     copyLengthFromLoader(loadable);
     for (SampleQueue sampleQueue : sampleQueues) {
-      sampleQueue.reset(true);
+      sampleQueue.reset();
     }
     if (enabledTrackCount > 0) {
       callback.onContinueLoadingRequested(this);
@@ -526,7 +534,7 @@ import java.util.Arrays;
       lastSeekPositionUs = 0;
       notifyReset = prepared;
       for (SampleQueue sampleQueue : sampleQueues) {
-        sampleQueue.reset(true);
+        sampleQueue.reset();
       }
       loadable.setLoadPosition(0, 0);
     }

library/core/src/main/java/com/google/android/exoplayer2/source/SampleQueue.java

@@ -98,9 +98,15 @@ public final class SampleQueue implements TrackOutput {
 
   /**
    * Resets the output.
-   *
-   * @param enable Whether the output should be enabled. False if it should be disabled.
    */
+  public void reset() {
+    reset(true);
+  }
+
+  /**
+   * @deprecated Use {@link #reset()}. Don't disable sample queues.
+   */
+  @Deprecated
   public void reset(boolean enable) {
     int previousState = state.getAndSet(enable ? STATE_ENABLED : STATE_DISABLED);
     clearSampleData();
@@ -169,8 +175,9 @@ public final class SampleQueue implements TrackOutput {
   // Called by the consuming thread.
 
   /**
-   * Disables buffering of sample data and metadata.
+   * @deprecated Don't disable sample queues.
    */
+  @Deprecated
   public void disable() {
     if (state.getAndSet(STATE_DISABLED) == STATE_ENABLED) {
       clearSampleData();

library/core/src/main/java/com/google/android/exoplayer2/source/chunk/ChunkSampleStream.java

@@ -203,9 +203,9 @@ public class ChunkSampleStream<T extends ChunkSource> implements SampleStream, S
       if (loader.isLoading()) {
         loader.cancelLoading();
       } else {
-        primarySampleQueue.reset(true);
+        primarySampleQueue.reset();
         for (SampleQueue embeddedSampleQueue : embeddedSampleQueues) {
-          embeddedSampleQueue.reset(true);
+          embeddedSampleQueue.reset();
         }
       }
     }
@@ -229,9 +229,9 @@ public class ChunkSampleStream<T extends ChunkSource> implements SampleStream, S
 
   @Override
   public void onLoaderReleased() {
-    primarySampleQueue.reset(true);
+    primarySampleQueue.reset();
     for (SampleQueue embeddedSampleQueue : embeddedSampleQueues) {
-      embeddedSampleQueue.reset(true);
+      embeddedSampleQueue.reset();
     }
   }
 
@@ -295,9 +295,9 @@ public class ChunkSampleStream<T extends ChunkSource> implements SampleStream, S
         loadable.startTimeUs, loadable.endTimeUs, elapsedRealtimeMs, loadDurationMs,
         loadable.bytesLoaded());
     if (!released) {
-      primarySampleQueue.reset(true);
+      primarySampleQueue.reset();
       for (SampleQueue embeddedSampleQueue : embeddedSampleQueues) {
-        embeddedSampleQueue.reset(true);
+        embeddedSampleQueue.reset();
       }
       callback.onContinueLoadingRequested(this);
     }