Parsoid does not use relative links anywhere anymore (T72743). There
is no reason for us to support this. And previous code allowed
"hrefPrefix" to be empty '' sometimes, which is scary, as it could
lead to XSS vulnerabilities if titles starting with 'JavaScript:' are
not handled correctly elsewhere.
Bug: T206357
Depends-On: I8728f63084902c76d1c61193be4367939b069f1a
Change-Id: I99be18877aae2b505cf261bd7cdef6cf0d7a8670
<a href="Foo%3F"> would dirty-diff to <a href="Foo?"> and also render
as such, pointing to the wrong page.
We also called decodeURIComponent() on the href twice, which can't
have been good.
Move URI decoding and underscore normalization into
getTargetDataFromHref(), and add rawTitle for callers that need it.
Put rawTitle in the origTitle attribute, so that equivalence
comparisons (decode(origTitle) === title) work as intended.
Bug: T145978
Change-Id: I29331a4ab0f8f7ef059c109f6813fa670a2c7390