Reduce ResourceLoader modules

Delete the following deprecated modules:
skins.minerva.base.styles, skins.minerva.mainMenu.styles,
skins.minerva.icons.wikimedia and skins.minerva.mainMenu.icons
And reorganize files for skins.minerva.styles

Bug: T266361
Change-Id: I35b1d9461edd63a1a5d488a2fdc6939547fd29ad

bundlesize.config.json

@@ -1,8 +1,4 @@
 [
-	{
-		"resourceModule": "skins.minerva.base.styles",
-		"maxSize": "9.6KB"
-	},
 	{
 		"resourceModule": "skins.minerva.styles",
 		"maxSize": "10.1KB"
@@ -15,22 +11,10 @@
 		"resourceModule": "mediawiki.hlist",
 		"maxSize": "0.3KB"
 	},
-	{
-		"resourceModule": "skins.minerva.icons.wikimedia",
-		"maxSize": "0.5KB"
-	},
-	{
-		"resourceModule": "skins.minerva.mainMenu.icons",
-		"maxSize": "0.4KB"
-	},
 	{
 		"resourceModule": "skins.minerva.icons",
 		"maxSize": "0.6KB"
 	},
-	{
-		"resourceModule": "skins.minerva.mainMenu.styles",
-		"maxSize": "1.1KB"
-	},
 	{
 		"resourceModule": "skins.minerva.scripts",
 		"maxSize": "14.5KB"

skin.json

@@ -332,25 +332,9 @@
 				"interface-core"
 			],
 			"styles": [
-				"resources/skins.minerva.base.styles/CSSCustomProperties.less",
-				"resources/skins.minerva.base.styles/skin.less",
-				"resources/skins.minerva.mainMenu.styles/index.less"
-			]
-		},
-		"skins.minerva.base.styles": {
-			"deprecated": "Retained for caching reasons. Please use skins.minerva.styles instead.",
-			"class": "MediaWiki\\ResourceLoader\\SkinModule",
-			"features": [
-				"normalize",
-				"accessibility",
-				"i18n-ordered-lists",
-				"content-body",
-				"content-tables",
-				"interface-core"
-			],
-			"styles": [
-				"resources/skins.minerva.base.styles/CSSCustomProperties.less",
-				"resources/skins.minerva.base.styles/skin.less"
+				"resources/skins.minerva.styles/CSSCustomProperties.less",
+				"resources/skins.minerva.styles/skin.less",
+				"resources/skins.minerva.styles/index.less"
 			]
 		},
 		"skins.minerva.content.styles.images": {
@@ -443,29 +427,6 @@
 				"watchlist"
 			]
 		},
-		"skins.minerva.icons.wikimedia": {
-			"deprecated": "Retained for caching reasons. Please use skins.minerva.icons instead.",
-			"selectorWithoutVariant": ".minerva-icon--{name}",
-			"useDataURI": false,
-			"defaultColor": "#54595d",
-			"class": "MediaWiki\\ResourceLoader\\OOUIIconPackModule",
-			"variants": [],
-			"useMaskImage": true,
-			"icons": [
-				"edit",
-				"wikiText",
-				"editLock",
-				"history",
-				"language",
-				"menu",
-				"search",
-				"userAvatar",
-				"userTalk",
-				"star",
-				"halfStar",
-				"unStar"
-			]
-		},
 		"skins.minerva.mainPage.styles": {
 			"styles": [
 				"resources/skins.minerva.mainPage.styles/common.less"
@@ -500,33 +461,6 @@
 			"variants": [],
 			"useDataURI": false
 		},
-		"skins.minerva.mainMenu.icons": {
-			"deprecated": "Retained for caching reasons. Please use skins.minerva.icons instead.",
-			"class": "MediaWiki\\ResourceLoader\\OOUIIconPackModule",
-			"variants": [],
-			"useMaskImage": true,
-			"selectorWithoutVariant": ".minerva-icon--{name}",
-			"defaultColor": "#54595d",
-			"useDataURI": false,
-			"icons": [
-				"die",
-				"heart",
-				"home",
-				"logIn",
-				"logOut",
-				"mapPin",
-				"settings",
-				"userContributions",
-				"unStar",
-				"watchlist"
-			]
-		},
-		"skins.minerva.mainMenu.styles": {
-			"deprecated": "Retained for caching reasons. Please use skins.minerva.styles instead.",
-			"styles": [
-				"resources/skins.minerva.mainMenu.styles/index.less"
-			]
-		},
 		"skins.minerva.loggedin.styles": {
 			"styles": [
 				"resources/skins.minerva.loggedin.styles/styles.less"