Use declared return type for inference of return and yield statements.

pkg/front_end/lib/src/fasta/builder/procedure_builder.dart

Index: pkg/front_end/lib/src/fasta/builder/procedure_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart b/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart
index 446ed241ed96d2a8aa04bba0daee99a4b3511835..008e94f1b8a22f8200b2ea30a2fff4f97f4e3778 100644
--- a/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart
@@ -7,7 +7,7 @@ library fasta.procedure_builder;
 // Note: we're deliberately using AsyncMarker and ProcedureKind from kernel
 // outside the kernel-specific builders. This is simpler than creating
 // additional enums.
-import 'package:kernel/ast.dart' show AsyncMarker, ProcedureKind;
+import 'package:kernel/ast.dart' show AsyncMarker, FunctionNode, ProcedureKind;

[ahe, 2017/05/24 15:36:39]

Could you move this to KernelProcedureBuilder?

[Paul Berry, 2017/05/24 16:20:16]

Acknowledged.  In light of your other suggestion, this change goes away.

 
 import 'builder.dart'
     show
@@ -60,6 +60,8 @@ abstract class ProcedureBuilder<T extends TypeBuilder> extends MemberBuilder {
 
   bool get isFactory => identical(ProcedureKind.Factory, kind);
 
+  FunctionNode get function;
+
   void set body(covariant statement);
 
   /// This is the formal parameter scope as specified in the Dart Programming