add global find keyword

src/background/reducers/find.js

@@ -0,0 +1,16 @@
+import actions from 'content/actions';
+
+const defaultState = {
+  keyword: null,
+};
+
+export default function reducer(state = defaultState, action = {}) {
+  switch (action.type) {
+  case actions.FIND_SET_KEYWORD:
+    return Object.assign({}, state, {
+      keyword: action.keyword,
+    });
+  default:
+    return state;
+  }
+}

src/background/reducers/index.js

@@ -1,12 +1,15 @@
 import settingReducer from './setting';
+import findReducer from './find';
 
 // Make setting reducer instead of re-use
 const defaultState = {
   setting: settingReducer(undefined, {}),
+  find: findReducer(undefined, {}),
 };
 
 export default function reducer(state = defaultState, action = {}) {
   return Object.assign({}, state, {
     setting: settingReducer(state.setting, action),
+    find: findReducer(state.find, action),
   });
 }