Revert "Print styles in Vector are no longer feature flagged"

This reverts commit c863b94302.

This breaks the MediaWiki Installer ui.

Bug: T183640
Change-Id: I9f249db503c4df6ab9d87b97d9f2d1dca80744ba

SkinVector.php

@@ -44,6 +44,10 @@ class SkinVector extends SkinTemplate {
 	/** @inheritDoc */
 	public function getPageClasses( $title ) {
 		$className = parent::getPageClasses( $title );
+		if ( $this->vectorConfig->get( 'VectorExperimentalPrintStyles' ) ) {
+			$className .= ' vector-experimental-print-styles';
+		}
+		$className .= ' vector-nav-directionality';
 		return $className;
 	}
 
@@ -70,6 +74,14 @@ class SkinVector extends SkinTemplate {
 			$this->enableResponsiveMode();
 		}
 
+		// Print styles are feature flagged.
+		// This flag can be removed when T169732 is resolved.
+		if ( $this->vectorConfig->get( 'VectorExperimentalPrintStyles' ) ) {
+			// Note, when deploying (T169732) we'll want to fold the stylesheet into
+			// skins.vector.styles and remove this module altogether.
+			$out->addModuleStyles( 'skins.vector.styles.experimental.print' );
+		}
+
 		$out->addModules( 'skins.vector.js' );
 	}
 

skin.json

@@ -38,7 +38,6 @@
 	"@note": "When modifying skins.vector.styles definition, make sure the installer still works",
 	"ResourceModules": {
 		"skins.vector.styles": {
-			"class": "Vector\\ResourceLoaderLessModule",
 			"targets": [ "desktop", "mobile" ],
 			"position": "top",
 			"styles": {
@@ -47,11 +46,17 @@
 				},
 				"screen-hd.less": {
 					"media": "screen and (min-width: 982px)"
-				},
-				"print.less": {}
+				}
 			}
 		},
-
+		"skins.vector.styles.experimental.print": {
+			"class": "Vector\\ResourceLoaderLessModule",
+			"targets": [ "desktop", "mobile" ],
+			"position": "top",
+			"styles": [
+				"print.less"
+			]
+		},
 		"skins.vector.styles.responsive": {
 			"targets": [ "desktop", "mobile" ],
 			"position": "top",
@@ -105,6 +110,8 @@
 	"config": {
 		"VectorUseSimpleSearch": true,
 		"VectorUseIconWatch": true,
+		"@VectorExperimentalPrintStyles": "Temporary config variable to feature flag new print styles (T154965)",
+		"VectorExperimentalPrintStyles": false,
 		"VectorResponsive": false,
 		"VectorPrintLogo": false
 	},