chore(web): Fix start:web (#488)

Author: tido64

example/examples/MergeItem.js

@@ -217,15 +217,21 @@ export default class Merge extends Component<Props, State> {
           <Button
             testID="setDelegate_button"
             title="Set native delegate"
-            disabled={!NativeModules.AsyncStorageTestSupport.test_setDelegate}
+            disabled={
+              !NativeModules.AsyncStorageTestSupport ||
+              !NativeModules.AsyncStorageTestSupport.test_setDelegate
+            }
             onPress={() =>
               NativeModules.AsyncStorageTestSupport.test_setDelegate(() => {})
             }
           />
           <Button
             testID="unsetDelegate_button"
             title="Unset native delegate"
-            disabled={!NativeModules.AsyncStorageTestSupport.test_unsetDelegate}
+            disabled={
+              !NativeModules.AsyncStorageTestSupport ||
+              !NativeModules.AsyncStorageTestSupport.test_unsetDelegate
+            }
             onPress={() =>
               NativeModules.AsyncStorageTestSupport.test_unsetDelegate(() => {})
             }

package.json

@@ -67,6 +67,7 @@
   "devDependencies": {
     "@babel/core": "^7.6.2",
     "@babel/runtime": "^7.6.2",
+    "@expo/webpack-config": "^0.12.0",
     "@react-native-community/bob": "^0.14.0",
     "@react-native-community/cli": "^4.5.1",
     "@react-native-community/cli-platform-android": "^4.5.1",

webpack.config.js

@@ -0,0 +1,7 @@
+const createExpoWebpackConfigAsync = require('@expo/webpack-config');
+
+module.exports = async function(env, argv) {
+  const config = await createExpoWebpackConfigAsync(env, argv);
+  config.resolve.alias['@react-native-async-storage/async-storage'] = __dirname;
+  return config;
+};