Use await/async on shared directory

src/shared/settings/storage.js

@@ -1,30 +1,28 @@
 import DefaultSettings from './default';
 import * as settingsValues from './values';
 
-const loadRaw = () => {
-  return browser.storage.local.get('settings').then(({ settings }) => {
-    if (!settings) {
-      return DefaultSettings;
-    }
-    return Object.assign({}, DefaultSettings, settings);
-  });
+const loadRaw = async() => {
+  let { settings } = await browser.storage.local.get('settings');
+  if (!settings) {
+    return DefaultSettings;
+  }
+  return Object.assign({}, DefaultSettings, settings);
 };
 
-const loadValue = () => {
-  return loadRaw().then((settings) => {
-    let value = JSON.parse(DefaultSettings.json);
-    if (settings.source === 'json') {
-      value = settingsValues.valueFromJson(settings.json);
-    } else if (settings.source === 'form') {
-      value = settingsValues.valueFromForm(settings.form);
-    }
-    if (!value.properties) {
-      value.properties = {};
-    }
-    return Object.assign({},
-      settingsValues.valueFromJson(DefaultSettings.json),
-      value);
-  });
+const loadValue = async() => {
+  let settings = await loadRaw();
+  let value = JSON.parse(DefaultSettings.json);
+  if (settings.source === 'json') {
+    value = settingsValues.valueFromJson(settings.json);
+  } else if (settings.source === 'form') {
+    value = settingsValues.valueFromForm(settings.form);
+  }
+  if (!value.properties) {
+    value.properties = {};
+  }
+  return Object.assign({},
+    settingsValues.valueFromJson(DefaultSettings.json),
+    value);
 };
 
 const save = (settings) => {

src/shared/versions/index.js

@@ -13,13 +13,12 @@ const notificationClickListener = (id) => {
   browser.notifications.onClicked.removeListener(notificationClickListener);
 };
 
-const checkUpdated = () => {
-  return storage.load().then((prev) => {
-    if (!prev) {
-      return true;
-    }
-    return manifest.version !== prev;
-  });
+const checkUpdated = async() => {
+  let prev = await storage.load();
+  if (!prev) {
+    return true;
+  }
+  return manifest.version !== prev;
 };
 
 const notify = () => {

src/shared/versions/storage.js

@@ -1,7 +1,6 @@
-const load = () => {
-  return browser.storage.local.get('version').then(({ version }) => {
-    return version;
-  });
+const load = async() => {
+  let { version } = await browser.storage.local.get('version');
+  return version;
 };
 
 const save = (version) => {