Optimize release of multiple allocations.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126799524

library/src/main/java/com/google/android/exoplayer/extractor/DefaultTrackOutput.java

@@ -550,9 +550,8 @@ public final class DefaultTrackOutput implements TrackOutput {
 
   private void clearSampleData() {
     infoQueue.clearSampleData();
-    while (!dataQueue.isEmpty()) {
+    allocator.release(dataQueue.toArray(new Allocation[dataQueue.size()]));
-      allocator.release(dataQueue.remove());
+    dataQueue.clear();
-    }
     allocator.trim();
     totalBytesDropped = 0;
     totalBytesWritten = 0;

library/src/main/java/com/google/android/exoplayer/upstream/Allocator.java

@@ -37,6 +37,13 @@ public interface Allocator {
    */
   void release(Allocation allocation);
 
+  /**
+   * Return an array of {@link Allocation}s.
+   *
+   * @param allocations The array of {@link Allocation}s being returned.
+   */
+  void release(Allocation[] allocations);
+
   /**
    * Hints to the {@link Allocator} that it should make a best effort to release any memory that it
    * has allocated beyond the target buffer size.

library/src/main/java/com/google/android/exoplayer/upstream/DefaultAllocator.java

@@ -29,6 +29,7 @@ public final class DefaultAllocator implements Allocator {
 
   private final int individualAllocationSize;
   private final byte[] initialAllocationBlock;
+  private final Allocation[] singleAllocationReleaseHolder;
 
   private int targetBufferSize;
   private int allocatedCount;
@@ -67,6 +68,7 @@ public final class DefaultAllocator implements Allocator {
     } else {
       initialAllocationBlock = null;
     }
+    singleAllocationReleaseHolder = new Allocation[1];
   }
 
   public synchronized void setTargetBufferSize(int targetBufferSize) {
@@ -92,14 +94,23 @@ public final class DefaultAllocator implements Allocator {
 
   @Override
   public synchronized void release(Allocation allocation) {
+    singleAllocationReleaseHolder[0] = allocation;
+    release(singleAllocationReleaseHolder);
+  }
+
+  @Override
+  public synchronized void release(Allocation[] allocations) {
+    if (availableCount + allocations.length >= availableAllocations.length) {
+      availableAllocations = Arrays.copyOf(availableAllocations,
+          Math.max(availableAllocations.length * 2, availableCount + allocations.length));
+    }
+    for (Allocation allocation : allocations) {
       // Weak sanity check that the allocation probably originated from this pool.
       Assertions.checkArgument(allocation.data == initialAllocationBlock
           || allocation.data.length == individualAllocationSize);
-    allocatedCount--;
-    if (availableCount == availableAllocations.length) {
-      availableAllocations = Arrays.copyOf(availableAllocations, availableAllocations.length * 2);
-    }
       availableAllocations[availableCount++] = allocation;
+    }
+    allocatedCount -= allocations.length;
     // Wake up threads waiting for the allocated size to drop.
     notifyAll();
   }