Support enabling of type inference with useKernel

pkg/compiler/lib/src/dart2js.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js.cmdline;
 
 import 'dart:async' show Future;
 import 'dart:convert' show UTF8, LineSplitter;
 import 'dart:io' show exit, File, FileMode, Platform, stdin, stderr;
 
@@ skipping 260 matching lines @@
       for (String category in categories) {
         if (!["Client", "Server"].contains(category)) {
           fail('Unsupported library category "$category", '
               'supported categories are: Client, Server, all');
         }
       }
     }
     passThrough('--categories=${categories.join(",")}');
   }
 
   void setPreviewDart2(String argument) {

[Siggi Cherem (dart-lang), 2017/08/25 14:45:46]

my fault, when I renamed "--preview-dart-2" to "--use-kernel" I seem to have
missed renaming this function. Could you rename it to setUseKernel?

BTW - apparently we should switch back the flag name, but before we do that we
need to fix test.py to pass it along

[Johnni Winther, 2017/08/25 16:50:41]

Done.
Acknowledged.

     useKernel = true;
+    // TODO(sigmund): remove once we support inlining and type-inference
+    // with `useKernel`.
+    options.add(Flags.disableInlining);
+    options.add(Flags.disableTypeInference);
     passThrough(argument);
   }
 
   void handleThrowOnError(String argument) {
     throwOnError = true;
     String parameter = extractParameter(argument, isOptionalArgument: true);
     if (parameter != null) {
       var count = int.parse(parameter);
       throwOnErrorCount = count;
     }
@@ skipping 819 matching lines @@
   @override
   void add(String event) {
     sb.write(event);
   }
 
   @override
   void close() {
     // Do nothing.
   }
 }