Previously, we rebased PRs on ews_revision, but after https://commits.webkit.org/257193@main, we started cherry-picking the contents of the PR branch so we had less changes for incremental builds. For that to work, we need to checkout the ews_revision for PRs too.
<rdar://problem/102981730>
Pull request: https://github.com/WebKit/WebKit/pull/7150
*** This bug has been marked as a duplicate of bug 248725 ***