FILE

PROBLEM

In 5.5 when doing doing a rename of a column ,we ignore the case between
old and new column names while comparing them,so if the change is just
the case then we don't even mark the field FIELD_IS_RENAMED ,we just update
the frm file ,but don't recreate the table as is the norm when alter is
used.This leads to inconsistency in the innodb data dictionary which causes
index creation to fail.

FIX

According to the documentation any innodb column rename should trigger
rebuild of the table. Therefore for innodb tables we will do a strcmp()
between the column names and if there is case change in column name
we will trigger a rebuild.