- Added a "reason" field to the "image_garbage_collected_total" metric, allowing administrators to differentiate between images that were collected for reasons "age" vs "space".
   ([#123345](https://github.com/kubernetes/kubernetes/pull/123345), [@haircommander](https://github.com/haircommander))

  fun setResponseCode(code: Int): MockResponse {
    val reason =
      when (code) {
        in 100..199 -> "Informational"
        in 200..299 -> "OK"
        in 300..399 -> "Redirection"
        in 400..499 -> "Client Error"
        in 500..599 -> "Server Error"
        else -> "Mock Response"
      }
    return apply { status = "HTTP/1.1 $code $reason" }
  }

  fun clearHeaders() =
    apply {

- Restored `NumPDBViolations` info of nodes, when `HTTPExtender ProcessPreemption`. This info will be used in subsequent filtering...

```json
{
    "reason": <string>
}
```

The reason message is returned to the client.

## Example Plugin Implementation

    val server = serverListener.assertOpen()
    clientListener.assertOpen()
    val reason = repeat('X', 124)
    assertFailsWith<IllegalArgumentException> {
      webSocket.close(1000, reason)
    }.also { expected ->
      assertThat(expected.message).isEqualTo("reason.size() > 123: $reason")
    }
    webSocket.close(1000, null)
    serverListener.assertClosing(1000, "")
    server.close(1000, null)

    tester.testConstructors(PatternFilenameFilter.class, Visibility.PACKAGE);
    tester.testStaticMethods(PatternFilenameFilter.class, Visibility.PACKAGE); // currently none

    // The reason that we skip this method is discussed in a comment on the method.
    tester.ignore(PatternFilenameFilter.class.getMethod("accept", File.class, String.class));

  // Last time the condition transitioned from one status to another.
  // +required
  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time lastTransitionTime = 4;

  // The reason for the condition's last transition.
  // +required
  optional string reason = 5;

  // A human readable message indicating details about the transition.
  // +required
  optional string message = 6;
}

// A list of StorageVersions.

   * not fail a test when an exception is thrown from one of its {@link TearDown} instances, but
   * this is subject to change. Also, {@code junit4.TearDownTestCase} will.
   *
   * @throws Exception for any reason. {@code TearDownTestCase} ensures that any exception thrown
   *     will not interfere with other TearDown operations.
   */
  void tearDown() throws Exception;

If we see fit, we can break these out to per-platform ones, or keep a hybrid approach to having global and platform-specific ADSs.

Our aim is to keep the process lightweight and approachable.

<!--- If suggesting a change/improvement, explain the difference from current behavior -->

## Possible Solution
<!--- Not obligatory, but suggest a fix/reason for the bug, -->
<!--- or ideas how to implement the addition or change -->

## Steps to Reproduce (for bugs)
<!--- Provide a link to a live example, or an unambiguous set of steps to -->