InnoDB would refuse to start up if there is a mismatch on
the size of the system tablespace files. However, before this
check is conducted, the system tablespace may already have been
heavily modified.

InnoDB should perform the size check as early as possible.

recv_recovery_from_checkpoint_finish():
Move the recv_apply_hashed_log_recs() call to
innobase_start_or_create_for_mysql().

innobase_start_or_create_for_mysql(): Test the mutex functionality
before doing anything else. Use a compile_time_assert() for a
sizeof() constraint. Check the size of the system tablespace as
early as possible.