MySQL 5.7.27 includes the following InnoDB changes:

Not applicable to MariaDB Server

Bug#28687608 EXCHANGE PARTITION GENERATING ERROR FOR ROW_FORMAT WHEN IT SHOULD NOT
The code changes are related to the InnoDB native partitioning (ha_innopart) that was introduced in MySQL 5.7. At the very end of the extended test main.partition_exchange there is a test for the scenario, and MariaDB is correctly returning ER_PARTITION_EXCHANGE_DIFFERENT_OPTION. Note: the test assumes default_storage_engine='innodb', which does not hold in MariaDB. It also uses WITH VALIDATION and WITHOUT VALIDATION syntax, which is missing from MariaDB.

Bug #29508001 MYSQL DEADLOCK AND BUGCHECK ON AARCH64 UNDER STRESS TEST
This attempts to fix something that was already fixed in MariaDB in MDEV-7148, MDEV-10813, and MDEV-11296.

Bug#28834208 row_log_table_apply_update*inplace_alter_table_impl*assertion failure:row0log.cc
MariaDB Server 10.2.11, 10.3.3 and later refuse online rebuild if indexed virtual columns exist (MDEV-13795, MDEV-14332) because various problems exist with the logging.

Bug#28104394 : INNODB 5.7 PRIMARY KEY SCAN LACK DATA
This is one more fix for the "optimized range scan" series of regressions caused by a change that we decided not to merge to MariaDB in MDEV-11751.

Not directly applicable to MariaDB

Bug #25289359 DML/DDL ON LARGE FULLTEXT TABLES CAUSE SEMAPHORE TIMEOUTS AND ASSERTION/SUICIDE
There is no test case, but there is debug instrumentation. We will investigate the scenario and track this change in MDEV-20126.

Applicable to MariaDB Server

Bug #29127203 VIRTUAL GENERATED COLUMN INDEX DATA INCONSISTENCY
This appears to fix something with virtual columns that are connected to FOREIGN KEY constraints. There is no test case.

BUG#29138644 PAGE CLEANER WILL SLEEP FOR LONG TIME IF CLOCK CHANGES and follow-up fix
This will be handled in MDEV-14154. The functions ut_time_us(), ut_time_ms(), ut_time() must be replaced with the use of a a monotonic timer, such as my_interval_timer().