KiteExternalLinks
What KiteDocView does with a link to an address outside the document, such as a web page or a mail address, when onLinkTap does not take it (#519).
EPUB Reading Systems 3.3 asks a reading system to open such a link in the browser, or in the mail app for mailto:, after it asks the reader. The viewer does that for every format: it asks with a small prompt in the view, and then opens the address through the platform's LocalUriHandler. Translate the prompt through LocalKiteViewerStrings. Pass externalLinks = null to KiteDocView and the viewer opens nothing.
Parameters
the schemes the viewer opens, in lower case. A document can name any scheme, file:, intent: and javascript: included, so the viewer ignores every scheme not in this set.
whether the viewer asks the reader before it opens an address.