The method now doesn't need unsafe in its signature because it no longer
accepts unsafe pointers as arguments. We move the unsafe marker to the
method itself.
Testing: I opened the browser and went to google.com; I ran some WPT
(IndexedDB) tests.
Fixes: #38361
---------
Signed-off-by: criskell <96352451+criskell@users.noreply.github.com>