RFR: 8356053: Test java/awt/Toolkit/Headless/HeadlessToolkit.java fails by timeout [v2]

[Sergey Bylokhov]

> The `java/awt/Toolkit/Headless/HeadlessToolkit.java` test covers some functionality of various methods in the `HeadlessToolkit` class, specifically whether these methods throw a `HeadlessException` or not. The image-related methods do not require access to a remote server via a URL; they can be tested using a URL pointing to a local file. This ensures that the test does not depend on `openjdk.org`.

Sergey Bylokhov has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - Merge branch 'openjdk:master' into JDK-8356053
 - 8356053: Test java/awt/Toolkit/Headless/HeadlessToolkit.java fails by timeout

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Changes:
  - all: https://git.openjdk.org/jdk/pull/25045/files
  - new: https://git.openjdk.org/jdk/pull/25045/files/c82bc634..fa2b3f36

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25045&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25045&range=00-01

  Stats: 16619 lines in 559 files changed: 9274 ins; 4478 del; 2867 mod
  Patch: https://git.openjdk.org/jdk/pull/25045.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25045/head:pull/25045

PR: https://git.openjdk.org/jdk/pull/25045