[1.6.x] Fixed #22321 -- Wrapped exceptions in _set_autocommit.

Refs #21202.

Backport of 3becac84 from master

django/db/backends/mysql/base.py

@@ -457,6 +457,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
             pass
 
     def _set_autocommit(self, autocommit):
+        with self.wrap_database_errors:
             self.connection.autocommit(autocommit)
 
     def disable_constraint_checking(self):

django/db/backends/oracle/base.py

@@ -625,6 +625,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
         pass
 
     def _set_autocommit(self, autocommit):
+        with self.wrap_database_errors:
             self.connection.autocommit = autocommit
 
     def check_constraints(self, table_names=None):

django/db/backends/postgresql_psycopg2/base.py

@@ -169,6 +169,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
             self.connection.set_isolation_level(isolation_level)
 
     def _set_autocommit(self, autocommit):
+        with self.wrap_database_errors:
             if self.psycopg2_version >= (2, 4, 2):
                 self.connection.autocommit = autocommit
             else:

django/db/backends/sqlite3/base.py

@@ -387,6 +387,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
             level = ''
         # 'isolation_level' is a misleading API.
         # SQLite always runs at the SERIALIZABLE isolation level.
+        with self.wrap_database_errors:
             self.connection.isolation_level = level
 
     def check_constraints(self, table_names=None):