Support enabling of type inference with useKernel

pkg/compiler/lib/src/dart2js.dart

Index: pkg/compiler/lib/src/dart2js.dart
diff --git a/pkg/compiler/lib/src/dart2js.dart b/pkg/compiler/lib/src/dart2js.dart
index 34c0a996466a742b6c114314c00a78b7ca63c2bc..ac8d65a78d59a9fa40148c5a0a4678fd210314cd 100644
--- a/pkg/compiler/lib/src/dart2js.dart
+++ b/pkg/compiler/lib/src/dart2js.dart
@@ -280,6 +280,10 @@ Future<api.CompilationResult> compile(List<String> argv) {
 
   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);
   }