Add more smart pointers to Geolocation.h and Geolocation.cpp
<rdar://problem/128497803>
Pull request: https://github.com/WebKit/WebKit/pull/28872
Committed 279237@main (71dc7942508f): <https://commits.webkit.org/279237@main> Reviewed commits have been landed. Closing PR #28872 and removing active labels.