Build:Event: Make sure all source modules' exports are used (#4648)

To achieve that, use `eslint-plugin-import`'s `no-unused-modules` rule.

Also, explicitly import `event/trigger.js` from `jquery.js`; so far it was
only imported from ajax.js, making it mistakenly skipped in the
`custom:slim,-deprecated` build.

src/.eslintrc.json

@@ -13,6 +13,10 @@
 	"rules": {
 		"import/extensions": [ "error", "always" ],
 		"import/no-cycle": "error",
+		"import/no-unused-modules": [ "error", {
+			"unusedExports": true,
+			"ignoreExports": [ "src/*.js" ]
+		} ],
 		"indent": [ "error", "tab", {
 			"outerIIFEBody": 0
 		} ]

src/core/init.js

@@ -118,5 +118,3 @@ init.prototype = jQuery.fn;
 
 // Initialize central reference
 rootjQuery = jQuery( document );
-
-export default init;

src/core/parseXML.js

@@ -20,5 +20,3 @@ jQuery.parseXML = function( data ) {
 	}
 	return xml;
 };
-
-export default jQuery.parseXML;

src/core/var/rhtml.js

@@ -1 +0,0 @@
-export default ( /HTML$/i );

src/event/trigger.js

@@ -190,5 +190,3 @@ jQuery.fn.extend( {
 		}
 	}
 } );
-
-export default jQuery;

src/jquery.js

@@ -11,6 +11,7 @@ import "./queue.js";
 import "./queue/delay.js";
 import "./attributes.js";
 import "./event.js";
+import "./event/trigger.js";
 import "./manipulation.js";
 import "./manipulation/_evalUrl.js";
 import "./wrap.js";

src/manipulation/_evalUrl.js

@@ -22,5 +22,3 @@ jQuery._evalUrl = function( url, options, doc ) {
 		}
 	} );
 };
-
-export default jQuery._evalUrl;