The patch affects only test suite and has the following changes:

1. On starting Instance Manager -- added code for waiting for guarded
mysqld instances to create PID files;
2. Polishing;
3. Move IM-related operations out of mtr_process.pl into new dedicated
for IM file -- mtr_im.pl


mysql-test/mysql-test-run.pl:
  1. Require new file with IM-related operations;
  2. Added timeout to wait for PID files of guarded instances;
  3. Polishing.
mysql-test/lib/mtr_process.pl:
  Move IM-related operations to new file.
mysql-test/lib/mtr_im.pl:
  File for IM-related operations.