Merge "Bump min supported HHVM version to 3.18.5"

diff --cc RELEASE-NOTES-1.31
index 30a174a,c9dc234..f8bca34
--- 1/RELEASE-NOTES-1.31
--- 2/RELEASE-NOTES-1.31
+++ b/RELEASE-NOTES-1.31
@@@ -163,12 -159,10 +163,12 @@@ changes to languages because of Phabric
  * The $statementsOnOwnLine parameter of JavaScriptMinifier::minify was removed.
    The corresponding configuration variable ($wgResourceLoaderMinifierStatementsOnOwnLine)
    has been deprecated since 1.27 and was removed as well.
 +* The HtmlFormatter class was removed (deprecated in 1.27). The namespaced
 +  HtmlFormatter\HtmlFormatter class should be used instead.
  
  == Compatibility ==
- MediaWiki 1.31 requires PHP 5.5.9 or later. There is experimental support for
- HHVM 3.6.5 or later.
+ MediaWiki 1.31 requires PHP 5.5.9 or later. Although HHVM 3.18.5 or later is supported,
+ it is generally advised to use PHP 5.5.9 or later for long term support.
  
  MySQL/MariaDB is the recommended DBMS. PostgreSQL or SQLite can also be used,
  but support for them is somewhat less mature. There is experimental support for

diff --cc includes/PHPVersionCheck.php
Simple merge