Bug#27510150: MYSQLDUMP FAILS FOR SPECIFIC --WHERE CLAUSES

Description: Mysqldump utility fails for specific clauses
used with the option, 'where'.

Analysis:- Method, "fix_identifier_with_newline()" that
prefixes all occurrences of newline char ('\n') in incoming
buffer does not verify the size of the buffer. The buffer in
which the incoming buffer is copied is limited to 2048 bytes
and the method does not try to allocate additional memory
for larger incoming buffers.

Fix:- Method, "fix_identifier_with_newline()" is modified
to fix this issue.