Add support for downloading M1 Mac (aarch64) Chromium (#2668)

Signed-off-by: Marques Lee <marques.lee@thoughtworks.com>

Signed-off-by: Marques Lee <marques.lee@thoughtworks.com>
Co-authored-by: Zabil Cheriya Maliackal <zabil@users.noreply.github.com>

lib/browserFetcher.js

@@ -29,11 +29,12 @@ const readline = require('readline');
 var url = require('url');
 const ProxyAgent = require('https-proxy-agent');
 const getProxyForUrl = require('proxy-from-env').getProxyForUrl;
-const supportedPlatforms = ['mac', 'linux', 'win32', 'win64'];
+const supportedPlatforms = ['mac', 'mac_arm', 'linux', 'win32', 'win64'];
 const DEFAULT_DOWNLOAD_HOST = 'https://storage.googleapis.com';
 const downloadURLs = {
   linux: '%s/chromium-browser-snapshots/Linux_x64/%d/%s.zip',
   mac: '%s/chromium-browser-snapshots/Mac/%d/%s.zip',
+  mac_arm: '%s/chromium-browser-snapshots/Mac_Arm/%d/%s.zip',
   win32: '%s/chromium-browser-snapshots/Win/%d/%s.zip',
   win64: '%s/chromium-browser-snapshots/Win_x64/%d/%s.zip',
 };
@@ -54,7 +55,7 @@ function archiveName(platform, revision) {
   if (platform === 'linux') {
     return 'chrome-linux';
   }
-  if (platform === 'mac') {
+  if (platform === 'mac' || platform === 'mac_arm') {
     return 'chrome-mac';
   }
   if (platform === 'win32' || platform === 'win64') {
@@ -79,7 +80,7 @@ class BrowserFetcher {
     if (!this._platform) {
       const platform = os.platform();
       if (platform === 'darwin') {
-        this._platform = 'mac';
+        this._platform = os.arch() === 'arm64' ? 'mac_arm' : 'mac';
       } else if (platform === 'linux') {
         this._platform = 'linux';
       } else if (platform === 'win32') {
@@ -180,7 +181,7 @@ class BrowserFetcher {
   revisionInfo(revision) {
     const folderPath = this._getFolderPath(revision);
     let executablePath = '';
-    if (this._platform === 'mac') {
+    if (this._platform === 'mac' || this._platform === 'mac_arm') {
       executablePath = path.join(
         folderPath,
         archiveName(this._platform, revision),