MySQL Replication - Accidentally Dropped Database on Slave
Yes, you should be fine.

You can DROP DATABASE IF EXISTS mydata; on the Master should replicate to the Slave, execute the IF EXISTS part on the Slave, do nothing, and be successful without erroring out.

I have done this before.

As an alternative, you could also run this on the Master:

SET sql_log_bin = 0;
DROP DATABASE mydata;
SET sql_log_bin = 1;


or

SET sql_log_bin = 0;
DROP DATABASE IF EXISTS mydata;
SET sql_log_bin = 1;


I have done this before as well.