public ScopedSpan startScopedSpan(String name) {
    return startScopedSpanWithParent(name, currentTraceContext.get());
  }
@Test void startScopedSpan_isInScope() {
    assertRealRoot(tracer.startScopedSpan("foo"));
    assertRealRoot(tracer.startScopedSpan("foo", deferDecision(), false));
  }