Migrate mac installer to delegate-driven model

chrome/installer/mac/app/main.m

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import <Foundation/Foundation.h>
+#import "MainDelegate.h"
 
-#import "Downloader.h"
-#import "OmahaCommunication.h"
-#import "OmahaXMLRequest.h"
-#import "SystemInfo.h"
+int main(int argc, const char* argv[]) {
+  MainDelegate* delegate = [[MainDelegate alloc] init];
+  [delegate talkToOmaha];
 
-// TODO: add a class that takes care of what main is doing now
-void talkToOmahaThenExecuteBlock(OmahaRequestCompletionHandler block) {
-  NSXMLDocument* requestBody = [OmahaXMLRequest createXMLRequestBody];
-  OmahaCommunication* messenger =
-      [[OmahaCommunication alloc] initWithBody:requestBody];
-  [messenger sendRequestWithBlock:block];
-}
-
-int main() {
-  talkToOmahaThenExecuteBlock(^(NSData* data, NSError* error) {
-    if (error) {
-      NSLog(@"%@", [error localizedDescription]);
-      return;
-    }
-    Downloader* download = [[Downloader alloc] init];
-    [download downloadChromeImageToDownloadsDirectory:data];
-  });
-
-  // [[NSRunLoop mainRunLoop] run];
-  [[NSRunLoop mainRunLoop]
-      runUntilDate:[NSDate dateWithTimeIntervalSinceNow:3]];
+  [[NSRunLoop mainRunLoop] run];
+  // [[NSRunLoop mainRunLoop]
+  //     runUntilDate:[NSDate dateWithTimeIntervalSinceNow:10]];
   return 1;
 }