Fix import after okhttp update.

Summary:
OkResponseCache moved packages in change
62321.

Change-Id: I2c08c4586405e767d1931ebc5f185c7916850fa1

Test Plan: fixes build

Reviewers: randall.rushing, Mustaavalkosta, synergy

Reviewed By: synergy

Differential Revision: http://review.codefirex.com/D268