We won't be able to turn on installapi phases in open source until this is fixed. Since there is no API from icu headers, we can make WTF filter these headers out of the filelist it generates, rather than improve the install-path-calculation logic in generate-tapi-filelist.py.
Pull request: https://github.com/WebKit/WebKit/pull/13931
<rdar://problem/109414018>
Committed 264550@main (abdeae2f7a08): <https://commits.webkit.org/264550@main> Reviewed commits have been landed. Closing PR #13931 and removing active labels.