Previously, due to the way the AngularJS and Angular clean-up processes
interfere with each other when removing an AngularJS element that
contains a downgraded Angular component, the data associated with the
host element of the downgraded component was not removed. This data was
kept in an internal AngularJS cache, which prevented the element and
component instance from being garbage-collected, leading to memory
leaks.
This commit fixes this by ensuring the element data is explicitly
removed when cleaning up a downgraded component.
NOTE:
This is essentially the equivalent of #26209 but for downgraded (instead
of upgraded) components.
Fixes#39911Closes#39921
PR Close#39965
6dc43a475b