T232864: Drop legacy hard-deprecated code from MediaWiki ahead of MediaWiki 1.35 release || NOTYETCREATED

This is a list of potential deprecated code to drop. Not all of it will be dropped before 1.36 (and we'll move entries to a parallel ticket for 1.37). Found by manually looking for hard deprecations; soft-deprecated code isn't listed here (yet?).

• From 1.26
  • MediaTransformOutput: streamFile
• From 1.27
  • Config: Setting $wgExternalDiffEngine to wikidiff or wikidiff3
  • AuthManager migration stuff
    • Calling User::createNew() with any of the params password, newpassword, newpass_time, or password_expires
    • Writing to $_SESSION
• From 1.28
  • UploadBase/UploadFromChunks::stashFile()
  • Linking things
    • The LinkBegin and LinkEnd hooks (r593874)
    • The DummyLinker class
• From 1.29
  • Message::getFormat() (r592765)
  • Config: Setting $wgDummyLanguageCodes
  • EmailUser hook returning a raw HTML string as an error
  • Having no manifest_version set in extension.json
• From 1.30
  • CommentStore migration temporary tables
• From 1.31
  • ParserOptions::setWrapOutputClass() without a wrapping class
  • The SimpleSearchResultWidget class
  • The SimpleSearchResultSetWidget class
  • Maintenance scripts calling Maintenance::error() with a $die value
• From 1.32
  • CommentStore image description migration temporary tables
  • All public properties of DifferenceEngine
  • Config: Setting $wgExternalDiffEngine to wikidiff2
  • EditPage::getContextTitle() with no title set
  • Constructing a HTMLInfoField with a string for the content when rawrow is set, instead of a FieldLayout
  • Using $input for the LogEventsListGetExtraInputs hook
  • Calling WikiPage::getDeletionUpdates() without a RevisionRecord or with a Content object
  • Calling ResourceLoaderWikiModule::getContentObj() without a ResourceLoader context
  • Calling Revision::getRevisionText() on a post-MCR schema database
  • Calling RevisionStore::getQueryInfo() for the text table on a post-MCR schema database
  • Constructing a BaseSearchResultSet without implementing extractResults
  • BaseSearchResultSet::next()
  • BaseSearchResultSet::rewind()
  • The SearchResultSet class
  • Calling SearchResultTrait::setExtensionData() with an array argument
  • SearchEngine::replacePrefixes()
  • Skin::getDynamicStylesheetQuery (T257991)
• From 1.33
  • Config: Setting $wgSquidPurgeUseHostHeader to false
  • Profiler::profileIn() (T241956)
  • Profiler::profileOut() (T241956)
  • Maintenance scripts calling Maintenance::getArg() without an $argId
  • Maintenance scripts calling Maintenance::hasArg() without an $argId