Initial commit for Chrome metainstaller on Mac.

chrome/installer/mac/app/DownloadDelegate.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 <assert.h>
+
+#import "DownloadDelegate.h"
+#import "Downloader.h"
+
+@implementation DownloadDelegate : NSObject
+
+// Skeleton of delegate method to provide download progress updates.
+// TODO: Make use of (totalBytesWritten/totalBytesExpectedToWrite)*100
+// to generate download progress percentage.
+- (void)URLSession:(NSURLSession*)session
+                 downloadTask:(NSURLSessionDownloadTask*)downloadTask
+                 didWriteData:(int64_t)bytesWritten
+            totalBytesWritten:(int64_t)totalBytesWritten
+    totalBytesExpectedToWrite:(int64_t)totalBytesExpectedToWrite {
+}
+
+// Delegate method to move downloaded disk image to user's Download directory.
+- (void)URLSession:(NSURLSession*)session
+                 downloadTask:(NSURLSessionDownloadTask*)downloadTask
+    didFinishDownloadingToURL:(NSURL*)location {
+  assert([location isFileURL]);
+  NSFileManager* manager = [[NSFileManager alloc] init];
+  NSURL* downloadsDirectory =
+      [[NSURL alloc] initFileURLWithPath:[Downloader getDownloadsFilePath]];
+  if ([manager fileExistsAtPath:location.path]) {
+    [manager copyItemAtURL:location toURL:downloadsDirectory error:nil];
+  } else {
+    // TODO: Error Handling
+  }
+}
+
+- (void)URLSession:(NSURLSession*)session
+                    task:(NSURLSessionTask*)task
+    didCompleteWithError:(NSError*)error {
+  // TODO: Error Handling
+}
+@end