Explicitly disable strict mode during the assisted dialing action.

Dialing is a critical path and there is no opportunity to perform
this action asynchronously.

Starting in P we could leverage the libphonenumber instance
that would live in PhoneGlobals and share that to warm up
the disk reads.

Bug: 70860471
Test: none. Unit tests do not trigger strict mode violations.
PiperOrigin-RevId: 183292426
Change-Id: I607c6af4d725272152f31e619367fdde5ed07302