DROP INDEX activity_accounts_account_id_idx;
DROP INDEX activity_accounts_activity_id_account_id_idx;
DROP INDEX activity_manager_node_id_idx;
DROP INDEX activity_manager_node_id_txid_idx;
DROP INDEX issuance_activity_assets_asset_id_idx;
DROP INDEX issuance_activity_assets_issuance_activity_id_asset_id_idx;
DROP INDEX issuance_activity_issuer_node_id_idx;
DROP INDEX issuance_activity_issuer_node_id_txid_idx;

DROP TABLE activity;
DROP TABLE activity_accounts;
DROP TABLE issuance_activity;
DROP TABLE issuance_activity_assets;

DROP INDEX activity_accounts_account_id_idx;
DROP INDEX activity_accounts_activity_id_account_id_idx;
DROP INDEX activity_manager_node_id_idx;
DROP INDEX activity_manager_node_id_txid_idx;
DROP INDEX issuance_activity_assets_asset_id_idx;
DROP INDEX issuance_activity_assets_issuance_activity_id_asset_id_idx;
DROP INDEX issuance_activity_issuer_node_id_idx;
DROP INDEX issuance_activity_issuer_node_id_txid_idx;

DROP TABLE
activity,
activity_accounts,
issuance_activity,
issuance_activity_assets;

Fix migration to drop all tables at once
Fix migration to drop all tables at once

Foreign key constraints between the tables were preventing the migration
from chain/chainprv#654 from running successfully.

Closes chain/chainprv#659.
Reviewers: da39a3ee5e6b4b0d3255bfef95601890afd80709@jeffomatic
