* Store the value of the page.page_restrictions field in Title::loadFromRow() and...

* Store the value of the page.page_restrictions field in Title::loadFromRow() and defers loading restrictions until when it's really needed; this reuses the Title::$mOldRestrictions member which is not used anywhere yet
* Removed $oldFashionedRestrictions parameter from Title::loadRestrictions*(); the only extension using it is LiquidThreads and it's using Title::newFromRow() to create the Title object, so the field is already cached (and this even allows to cache that field when there's no row for that page in the page_restrictions table)
* Also reset $mTouched and $mIsNew members on resetArticleId() calls
* Updated FakeTitle a bit