[ Merge of http://go/wvgerrit/149130 ] When re-initializing OEMCrypto for testing purposes, the UsageTableHeader must be reset as well. This is to inform future sessions to load or create a new header before creating new entries. Bug: 219075437 Test: request_license_test and MediaDrmTests GTS Change-Id: Ie8bc72bc7ea079d21587e114223fcb67547c756a