made DROP VIEW to continue on error and report an aggregated error 
 at its end. This makes it similar to DROP TABLE.


mysql-test/r/view.result:
  Bug #11551: Asymmetric + undocumented behaviour of DROP VIEW and DROP TABLE
   - test case
   - changed error message
mysql-test/t/view.test:
  Bug #11551: Asymmetric + undocumented behaviour of DROP VIEW and DROP TABLE
   - test case
sql/sql_view.cc:
  Bug #11551: Asymmetric + undocumented behaviour of DROP VIEW and DROP TABLE
   - made DROP VIEW to continue on error and report an aggregated error