Add an endpoint to the core REST API to return the list of
media files embedded in a page, including certain metadata
for each media file.
Bug: T236169
Change-Id: I3188848ee7de365d209dfb7da5b885313e9f705b
We currently show SVGs in default languages unless overridden with
lang=... URL parameter (and we have UI for setting it). This change
makes it display thumbnails in wiki language, if translation is available.
Bug: T210814
Change-Id: Ieb0b5e9e27f45b71ef119bb3c1d3f2cd4d7100e5