mw.Title: Rewrite from scratch (porting logic from Title.php)
Changes:
* Add support for fragments.
* Use wgLegalTitleChars instead of the old clean() method
that stripped out characters instead of throwing an exception.
* Implemented various other parts of Title.php to make it more
strict like Title.php. It is still slightly looser, but it
now takes care of the following that Title.php did already:
- Directory patterns ("../" etc.)
- Extra initial colons
- Titles in NS_TALK that don't round-trip to NS_MAIN
- 3 or more consecutive tildes
- Limited title size (255 bytes)
* Extracted parsing logic into a private static #parse method
and introduced mw.Title.newFromText (a constructor that returns
null|Title instead of throwing an exception).
* Extended test suite to cover the added features and fixed bugs.
* Since the PHP test suite was lacking these, added them there
as well.
Bug fixes:
* Fragments are now excluded from the title instead of causing
the input to be invalid or malformed (e.g. "Foo#bar" was being
normalised to "Foo_bar").
* ".com" now parses and round-trips properly. The extension and
rest of title are still separated, but only at the very end
after all other processing, so though title cannot be empty,
since we only do a lazy split afterwards, it will split into
title="", ext="com" internally and join back together when
needed (bug 38081).
* "Example.js " (trailing space after extension) was previously
incorrectly parsed as title=Example.js,ext=null.
* "Foo bar" (multiple consecutive spaces) was transformed
into 1 space correctly, but "Foo___bar" was not. This has been
fixed to match the PHP implementation (it merges underscores
and whitespace of any kind).
Clean up:
* Removed various redundant private helper methods.
* Removed fixNsId as getNsIdByName uses wgNamespaceIds which
always yields a valid value. The fixNsId was verifying
something that was already valid.
* Yoda conditional in Title.php, got rid of.
* Use newFromText in jquery.byteLimit.test. It was previously
using a very basic invalid test (=== '') and no try-catch.
Since we're getting more strict, typing 'User:' results in
an invalid title, which should result in the same behaviour
as it previously did for the lazy === '' check.
Bug: 38081
Change-Id: Ief1c11dabadc2f822065c40be91e04d655933e4f