📝 Match variable names

[ci skip]

docs/tutorial/quick-start.md

@@ -88,24 +88,24 @@ const {BrowserWindow} = electron;
 
 // Keep a global reference of the window object, if you don't, the window will
 // be closed automatically when the JavaScript object is garbage collected.
-let mainWindow;
+let win;
 
 function createWindow() {
   // Create the browser window.
-  mainWindow = new BrowserWindow({width: 800, height: 600});
+  win = new BrowserWindow({width: 800, height: 600});
 
   // and load the index.html of the app.
-  mainWindow.loadURL(`file://${__dirname}/index.html`);
+  win.loadURL(`file://${__dirname}/index.html`);
 
   // Open the DevTools.
-  mainWindow.webContents.openDevTools();
+  win.webContents.openDevTools();
 
   // Emitted when the window is closed.
-  mainWindow.on('closed', () => {
+  win.on('closed', () => {
     // Dereference the window object, usually you would store windows
     // in an array if your app supports multi windows, this is the time
     // when you should delete the corresponding element.
-    mainWindow = null;
+    win = null;
   });
 }
 
@@ -126,7 +126,7 @@ app.on('window-all-closed', () => {
 app.on('activate', () => {
   // On OS X it's common to re-create a window in the app when the
   // dock icon is clicked and there are no other windows open.
-  if (mainWindow === null) {
+  if (win === null) {
     createWindow();
   }
 });