[iOS] Add Sync Query Logic For Async Safe Browsing

This CL adds the sync portion for what's needed in async safe browsing.
This is a preliminary CL to break implementation into smaller more
manageable CLs. Although these changes look similar to the default
behavior, later implementations will refactor methods to take async
checks into account within sync query logic.

Bug: 41491791
Change-Id: I6eedde96955e23fbc815a096831a41b4a3f38dfd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5527554
Commit-Queue: Joemer Ramos <joemerramos@chromium.org>
Reviewed-by: Ali Juma <ajuma@chromium.org>
Code-Coverage: findit-for-me@appspot.gserviceaccount.com <findit-for-me@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1305323}