Convert remaining uses of alloc] init] to new]

Summary: public

We moved to using `new` instead of `alloc] init` but there was still some calls
left.

Reviewed By: javache

Differential Revision: D2604679

fb-gh-sync-id: ff7300ecbedb55dd5e93873592598810c9b87808

local-cli/generator-ios/templates/app/AppDelegate.m

@@ -47,7 +47,7 @@
                                                    launchOptions:launchOptions];
 
   self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
-  UIViewController *rootViewController = [[UIViewController alloc] init];
+  UIViewController *rootViewController = [UIViewController new];
   rootViewController.view = rootView;
   self.window.rootViewController = rootViewController;
   [self.window makeKeyAndVisible];