in different default schema.

In strict mode, when data truncation or conversion happens,
THD::killed is set to THD::KILL_BAD_DATA.

This is abuse of KILL mechanism to guarantee that execution
of statement is aborted.

The stored procedures execution, on the other hand,
upon detection that a connection was killed, would
terminate immediately, without trying to restore the caller's
context, in particular, restore the caller's current schema.

The fix is, when terminating a stored procedure execution,
to only bypass cleanup if the entire connection was killed,
not in case of other forms of KILL.


mysql-test/r/sp-bugs.result:
  Added result for a test case for bug#54375.
mysql-test/t/sp-bugs.test:
  Added test case for bug#54375.
sql/sp_head.cc:
  sp_head::execute modified: restore saved current db if
  connection is not killed.