Merge pull request #15890 from civicrm/5.20

5.20

diff --cc CRM/Contribute/Form/AdditionalPayment.php
Simple merge

diff --cc CRM/Core/BAO/FinancialTrxn.php
Simple merge

diff --cc CRM/Report/Form/Member/Summary.php
Simple merge

diff --cc api/v3/Payment.php
Simple merge

diff --cc templates/CRM/Contribute/Form/AdditionalPayment.tpl
Simple merge

diff --cc tests/phpunit/api/v3/PaymentTest.php
Simple merge

diff --cc tests/phpunit/api/v3/SyntaxConformanceTest.php
Simple merge