Fix WPT test import/masking-path-06-b-manual.svg crash.
Pull request: https://github.com/WebKit/WebKit/pull/20046
Committed 270321@main (559334c54532): <https://commits.webkit.org/270321@main> Reviewed commits have been landed. Closing PR #20046 and removing active labels.
<rdar://problem/118058876>