In 264455@main, we introduced `WebPageProxy::dispatchMouseDidMoveOverElementAsynchronously`, which asks to perform `WebPageProxy::mouseDidMoveOverElement` at a future time. It turns out there's a null access on `m_pageClient` when we then call into `WebPageProxy::setToolTip`, which happens because we hold a `WeakPtr<PageClient>` instance to the `PageClient` object, meaning there are no guarantees on the PageClient instance's lifetime. We should make sure this null deference does not happen.
rdar://110501313
Pull request: https://github.com/WebKit/WebKit/pull/15113
Committed 265456@main (46b03afa5a23): <https://commits.webkit.org/265456@main> Reviewed commits have been landed. Closing PR #15113 and removing active labels.