Reinsert return.

sdk/lib/_internal/compiler/implementation/elements/modelx.dart

Index: sdk/lib/_internal/compiler/implementation/elements/modelx.dart
diff --git a/sdk/lib/_internal/compiler/implementation/elements/modelx.dart b/sdk/lib/_internal/compiler/implementation/elements/modelx.dart
index 02d2320f6b05e668b74f2a74806f246f100d325b..909c4c63f152df2363fa3cbd51e9c024077c96a4 100644
--- a/sdk/lib/_internal/compiler/implementation/elements/modelx.dart
+++ b/sdk/lib/_internal/compiler/implementation/elements/modelx.dart
@@ -1228,7 +1228,8 @@ class FunctionElementX extends ElementX implements FunctionElement {
     if (super.isAbstract(compiler)) return true;
     if (modifiers.isExternal()) return false;
     if (isFunction() || isAccessor()) {
-      compiler.withCurrentElement(this, () => !parseNode(compiler).hasBody());
+      return compiler.withCurrentElement(this,
+          () => !parseNode(compiler).hasBody());
     }
     return false;
   }