Auto merge of #17862 - asajeffrey:script-paint-worklet-border, r=pcwalton

Implemented paint worklets drawing to a border.

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Allow paint worklets to draw to a border.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #17451.
- [X] These changes do not require tests because the existing css-paint-api test check this (but annoyingly, all fail for other reasons)

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tests/wpt/mozilla/meta/mozilla/css-paint-api/geometry-border-image-001.html.ini

@@ -1,4 +1,4 @@
 [geometry-border-image-001.html]
   type: reftest
   expected: FAIL
-  bug: https://github.com/servo/servo/issues/1767
+  bug: https://github.com/servo/servo/issues/17861

tests/wpt/mozilla/meta/mozilla/css-paint-api/geometry-border-image-002.html.ini

@@ -1,4 +1,4 @@
 [geometry-border-image-002.html]
   type: reftest
   expected: FAIL
-  bug: https://github.com/servo/servo/issues/17451
+  bug: https://github.com/servo/servo/issues/17860

tests/wpt/mozilla/meta/mozilla/css-paint-api/geometry-border-image-003.html.ini

@@ -1,4 +1,4 @@
 [geometry-border-image-003.html]
   type: reftest
   expected: FAIL
-  bug: https://github.com/servo/servo/issues/17451
+  bug: https://github.com/servo/servo/issues/17860

tests/wpt/mozilla/meta/mozilla/css-paint-api/geometry-border-image-004.html.ini

@@ -1,4 +1,4 @@
 [geometry-border-image-004.html]
   type: reftest
   expected: FAIL
-  bug: https://github.com/servo/servo/issues/17451
+  bug: https://github.com/servo/servo/issues/17860

tests/wpt/mozilla/meta/mozilla/css-paint-api/geometry-border-image-005.html.ini

@@ -1,4 +1,4 @@
 [geometry-border-image-005.html]
   type: reftest
   expected: FAIL
-  bug: https://github.com/w3c/web-platform-tests/issues/6610
+  bug: https://github.com/servo/servo/issues/17860