or request state must be added through MakeGlobalVariablesScript instead.
&$vars: array( variable name => value )
+'ResourceLoaderGetLessVars': Called in ResourceLoader::getLessVars after variables
+from $wgResourceLoaderLESSVars are added. Can be used to add context-based variables.
+&$lessVars: array of variables already added
+
'ResourceLoaderRegisterModules': Right before modules information is required,
such as when responding to a resource
loader request or generating HTML output.