Note: this contains a b/c incompatible change to
SlotRoleHandler, but it's never used in any extensions
and never was used.
Change-Id: I898ab18467f7f8c605a579cc6236859b9d86c7f5
This causes RevisionStore to use FallbackContent instances to represent
content for which no content handler is defined.
This may happen when loading revisions using a model that was defined
by an extension that has since been uninstalled.
Bug: T220594
Bug: T220793
Bug: T228921
Change-Id: I5cc9e61223ab22406091479617b077512aa6ae2d
These new classes provide a mechanism for defining the
behavior of slots, like the content models it supports.
This acts as an extension point for extensions that need
to define custom slots, like the MediaInfo extension
for the SDC project.
Bug: T194046
Change-Id: Ia20c98eee819293199e541be75b5521f6413bc2f