Implement adding a user to a list from their profile (#9062)

* Add add user to list from thier profile

* Fix listAdderCss

app/javascript/mastodon/reducers/list_adder.js

@@ -0,0 +1,47 @@
+import { Map as ImmutableMap, List as ImmutableList } from 'immutable';
+import {
+  LIST_ADDER_RESET,
+  LIST_ADDER_SETUP,
+  LIST_ADDER_LISTS_FETCH_REQUEST,
+  LIST_ADDER_LISTS_FETCH_SUCCESS,
+  LIST_ADDER_LISTS_FETCH_FAIL,
+  LIST_EDITOR_ADD_SUCCESS,
+  LIST_EDITOR_REMOVE_SUCCESS,
+} from '../actions/lists';
+
+const initialState = ImmutableMap({
+  accountId: null,
+
+  lists: ImmutableMap({
+    items: ImmutableList(),
+    loaded: false,
+    isLoading: false,
+  }),
+});
+
+export default function listAdderReducer(state = initialState, action) {
+  switch(action.type) {
+  case LIST_ADDER_RESET:
+    return initialState;
+  case LIST_ADDER_SETUP:
+    return state.withMutations(map => {
+      map.set('accountId', action.account.get('id'));
+    });
+  case LIST_ADDER_LISTS_FETCH_REQUEST:
+    return state.setIn(['lists', 'isLoading'], true);
+  case LIST_ADDER_LISTS_FETCH_FAIL:
+    return state.setIn(['lists', 'isLoading'], false);
+  case LIST_ADDER_LISTS_FETCH_SUCCESS:
+    return state.update('lists', lists => lists.withMutations(map => {
+      map.set('isLoading', false);
+      map.set('loaded', true);
+      map.set('items', ImmutableList(action.lists.map(item => item.id)));
+    }));
+  case LIST_EDITOR_ADD_SUCCESS:
+    return state.updateIn(['lists', 'items'], list => list.unshift(action.listId));
+  case LIST_EDITOR_REMOVE_SUCCESS:
+    return state.updateIn(['lists', 'items'], list => list.filterNot(item => item === action.listId));
+  default:
+    return state;
+  }
+};