joinUninterruptibly(interruptingThread, 2500, MILLISECONDS);
            Thread.interrupted();
            if (interruptingThread.isAlive()) {
              // This will be hidden by test-output redirection:
              logger.severe("InterruptenatorTask did not exit; future tests may be affected");
              /*
               * This won't do any good under JUnit 3, but I'll leave it around in

     * - Temporarily change this test:
     * --- Comment out assertEquals.
     * --- System.out.println(input + " " + simplifyPath(input));
     * --- fail(). (If the test were to pass, its output would be hidden.)
     * - Run the test.
     * - Pull the relevant lines of output from the test into a testcases file.
     * - Test the output:
     * --- cat testcases | while read L; do
     *       X=($L)

     * - Temporarily change this test:
     * --- Comment out assertEquals.
     * --- System.out.println(input + " " + simplifyPath(input));
     * --- fail(). (If the test were to pass, its output would be hidden.)
     * - Run the test.
     * - Pull the relevant lines of output from the test into a testcases file.
     * - Test the output:
     * --- cat testcases | while read L; do
     *       X=($L)

     *
     * - _shouldn't_ be null, so we don't annotate it with @Nullable
     *
     * - _can_ be null without causing a runtime failure (because we don't want the interesting
     *   details of precondition failure to be hidden by an exception we throw about an unexpectedly
     *   null _failure message_)
     *
     * That combination upsets NullPointerTester, which wants any call that passes null for a

     * @param closingExecutor the object will be closed on this executor
     * @return the first argument
     */
    @CanIgnoreReturnValue
    @ParametricNullness
    // TODO(b/163345357): Widen bound to AutoCloseable once we require API Level 19.
    public <C extends @Nullable Object & @Nullable Closeable> C eventuallyClose(
        @ParametricNullness C closeable, Executor closingExecutor) {