Merge branch 'master' into tr/codebase-overview

Author: thayashi

content/blog/2019-02-23-is-react-translated-yet.md

@@ -43,7 +43,7 @@ We started of with an initial trial period of three languages: Spanish, Japanese
 
 After the trial period, we were ready to accept more languages. I created [a script](https://github.com/reactjs/reactjs.org-translation/blob/master/scripts/create.js) to automate the creation of the new language repo, and a site, [Is React Translated Yet?](https://isreacttranslatedyet.com), to track progress on the different translations. We started *10* new translations on our first day alone!
 
-Because of the automation, the rest of the maintance went mostly smoothly. We eventually created a [Slack channel](https://rt-slack-invite.herokuapp.com) to make it easier for translators to share information, and I released a guide solidifying the [responsibilities of maintainers](https://github.com/reactjs/reactjs.org-translation/blob/master/maintainer-guide.md). Allowing translators to talk with each other was a great boon -- for example, the Arabic, Persian, and Hebrew translations were able to talk to each other in order to get [right-to-left text](https://en.wikipedia.org/wiki/Right-to-left) working!
+Because of the automation, the rest of the maintenance went mostly smoothly. We eventually created a [Slack channel](https://rt-slack-invite.herokuapp.com) to make it easier for translators to share information, and I released a guide solidifying the [responsibilities of maintainers](https://github.com/reactjs/reactjs.org-translation/blob/master/maintainer-guide.md). Allowing translators to talk with each other was a great boon -- for example, the Arabic, Persian, and Hebrew translations were able to talk to each other in order to get [right-to-left text](https://en.wikipedia.org/wiki/Right-to-left) working!
 
 ## The Bot {#the-bot}
 

content/docs/addons-test-utils.md

@@ -53,7 +53,7 @@ var ReactTestUtils = require('react-dom/test-utils'); // ES5 with npm
 例えば、次のような `Counter` コンポーネントがあるとしましょう：
 
 ```js
-class App extends React.Component {
+class Counter extends React.Component {
   constructor(props) {
     super(props);
     this.state = {count: 0};