Revert "Use native async/await support in pub."

sdk/lib/_internal/pub_generated/lib/src/oauth2.dart

Index: sdk/lib/_internal/pub_generated/lib/src/oauth2.dart
diff --git a/sdk/lib/_internal/pub/lib/src/oauth2.dart b/sdk/lib/_internal/pub_generated/lib/src/oauth2.dart
similarity index 87%
copy from sdk/lib/_internal/pub/lib/src/oauth2.dart
copy to sdk/lib/_internal/pub_generated/lib/src/oauth2.dart
index 8de110c00b55f60e55446e2ee1c54cc1e0289d67..6edac4b3596a4f703f7c099e19e51e2108231929 100644
--- a/sdk/lib/_internal/pub/lib/src/oauth2.dart
+++ b/sdk/lib/_internal/pub_generated/lib/src/oauth2.dart
@@ -21,8 +21,8 @@ import 'utils.dart';
 export 'package:oauth2/oauth2.dart';
 
 /// The pub client's OAuth2 identifier.
-final _identifier = '818368855108-8grd2eg9tj9f38os6f1urbcvsq399u8n.apps.'
-    'googleusercontent.com';
+final _identifier =
+    '818368855108-8grd2eg9tj9f38os6f1urbcvsq399u8n.apps.' 'googleusercontent.com';
 
 /// The pub client's OAuth2 secret.
 ///
@@ -38,7 +38,7 @@ final _secret = 'SWeqj8seoJW0w7_CpEPFLX0K';
 /// [Google OAuth2 documentation]: https://developers.google.com/accounts/docs/OAuth2WebServer#offline
 final authorizationEndpoint = Uri.parse(
     'https://accounts.google.com/o/oauth2/auth?access_type=offline'
-    '&approval_prompt=force');
+        '&approval_prompt=force');
 
 /// The URL from which the pub client will request an access token once it's
 /// been authorized by the user.
@@ -91,8 +91,9 @@ Future withClient(SystemCache cache, Future fn(Client client)) {
     });
   }).catchError((error) {
     if (error is ExpirationException) {
-      log.error("Pub's authorization to upload packages has expired and "
-          "can't be automatically refreshed.");
+      log.error(
+          "Pub's authorization to upload packages has expired and "
+              "can't be automatically refreshed.");
       return withClient(cache, fn);
     } else if (error is AuthorizationException) {
       var message = "OAuth2 authorization failed";
@@ -117,8 +118,8 @@ Future<Client> _getClient(SystemCache cache) {
     var credentials = _loadCredentials(cache);
     if (credentials == null) return _authorize();
 
-    var client = new Client(_identifier, _secret, credentials,
-        httpClient: httpClient);
+    var client =
+        new Client(_identifier, _secret, credentials, httpClient: httpClient);
     _saveCredentials(cache, client.credentials);
     return client;
   });
@@ -140,15 +141,17 @@ Credentials _loadCredentials(SystemCache cache) {
 
     var credentials = new Credentials.fromJson(readTextFile(path));
     if (credentials.isExpired && !credentials.canRefresh) {
-      log.error("Pub's authorization to upload packages has expired and "
-          "can't be automatically refreshed.");
+      log.error(
+          "Pub's authorization to upload packages has expired and "
+              "can't be automatically refreshed.");
       return null; // null means re-authorize.
     }
 
     return credentials;
   } catch (e) {
-    log.error('Warning: could not load the saved OAuth2 credentials: $e\n'
-        'Obtaining new credentials...');
+    log.error(
+        'Warning: could not load the saved OAuth2 credentials: $e\n'
+            'Obtaining new credentials...');
     return null; // null means re-authorize.
   }
 }
@@ -195,20 +198,21 @@ Future<Client> _authorize() {
       // Closing the server here is safe, since it will wait until the response
       // is sent to actually shut down.
       server.close();
-      chainToCompleter(grant.handleAuthorizationResponse(queryToMap(queryString)),
+      chainToCompleter(
+          grant.handleAuthorizationResponse(queryToMap(queryString)),
           completer);
 
       return new shelf.Response.found('http://pub.dartlang.org/authorized');
     });
 
     var authUrl = grant.getAuthorizationUrl(
-        Uri.parse('http://localhost:${server.port}'), scopes: _scopes);
+        Uri.parse('http://localhost:${server.port}'),
+        scopes: _scopes);
 
     log.message(
         'Pub needs your authorization to upload packages on your behalf.\n'
-        'In a web browser, go to $authUrl\n'
-        'Then click "Allow access".\n\n'
-        'Waiting for your authorization...');
+            'In a web browser, go to $authUrl\n' 'Then click "Allow access".\n\n'
+            'Waiting for your authorization...');
   });
 
   return completer.future.then((client) {