String message = "Waited " + timeout + " " + unit.toString().toLowerCase(Locale.ROOT);
    // Only report scheduling delay if larger than our spin threshold - otherwise it's just noise
    if (remainingNanos + SPIN_THRESHOLD_NANOS < 0) {
      // We over-waited for our timeout.
      message += " (plus ";
      long overWaitNanos = -remainingNanos;
      long overWaitUnits = unit.convert(overWaitNanos, TimeUnit.NANOSECONDS);

import java.util.logging.Level;
import java.util.logging.Logger;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Emulation for AbstractFuture in GWT. */
@SuppressWarnings("nullness") // TODO(b/147136275): Remove once our checker understands & and |.
@ElementTypesAreNonnullByDefault
public abstract class AbstractFuture<V extends @Nullable Object> extends InternalFutureFailureAccess
    implements ListenableFuture<V> {