remove unused actions and fix test

src/content/reducers/find.js

@@ -1,21 +1,12 @@
 import actions from 'content/actions';
 
 const defaultState = {
-  enabled: false,
   keyword: '',
   found: false,
 };
 
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
-  case actions.FIND_SHOW:
-    return Object.assign({}, state, {
-      enabled: true,
-    });
-  case actions.FIND_HIDE:
-    return Object.assign({}, state, {
-      enabled: false,
-    });
   case actions.FIND_SET_KEYWORD:
     return Object.assign({}, state, {
       keyword: action.keyword,