Implement type inference for asserts in constructor initializers.

pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart

Index: pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
index 5fdd6102030b16d42cdd7a623de7a6b0ec359762..0256ac57f30164b0766faad26a87cfb01ebf605c 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
@@ -90,6 +90,12 @@ class TypeInferenceListener
   void asExpressionExit(AsExpression expression, DartType inferredType) =>
       genericExpressionExit("asExpression", expression, inferredType);
 
+  void assertInitializerEnter(LocalInitializer initializer) =>
+      genericInitializerEnter("assertInitializer", initializer);
+
+  void assertInitializerExit(LocalInitializer initializer) =>
+      genericInitializerExit("assertInitializer", initializer);
+
   void assertStatementEnter(AssertStatement statement) =>
       genericStatementEnter('assertStatement', statement);