Migrate DDC to the new analysis driver.

pkg/dev_compiler/tool/build_sdk.dart

Index: pkg/dev_compiler/tool/build_sdk.dart
diff --git a/pkg/dev_compiler/tool/build_sdk.dart b/pkg/dev_compiler/tool/build_sdk.dart
index 9761f1ddbe027b413ce8375ee424f881d9c833fe..360e2e8d1ffa0fd501699881ae7af05c2c9fa7f9 100644
--- a/pkg/dev_compiler/tool/build_sdk.dart
+++ b/pkg/dev_compiler/tool/build_sdk.dart
@@ -13,7 +13,7 @@ import 'dart:io';
 
 import 'package:dev_compiler/src/compiler/command.dart';
 
-main(List<String> arguments) {
+main(List<String> arguments) async {
   var args = [
     '--unsafe-force-compile',
     '--no-source-map',
@@ -54,6 +54,6 @@ main(List<String> arguments) {
     'dart:web_sql'
   ]);
 
-  var result = compile(args);
+  var result = await compile(args);
   exit(result);
 }