Handle const constructor invocation in kernel_impact.

tests/compiler/dart2js/kernel/visitor_test.dart

Index: tests/compiler/dart2js/kernel/visitor_test.dart
diff --git a/tests/compiler/dart2js/kernel/visitor_test.dart b/tests/compiler/dart2js/kernel/visitor_test.dart
index 1c7c20e0d190b2705a1a4db9265b18c79e1366b6..68a6f899cdf235620bc90ddba47cd6b10b21e3f5 100644
--- a/tests/compiler/dart2js/kernel/visitor_test.dart
+++ b/tests/compiler/dart2js/kernel/visitor_test.dart
@@ -41,8 +41,8 @@ main(List<String> arguments) {
         StringBuffer buffer = new StringBuffer();
         Program program = backend.kernelTask.buildProgram(library);
         new MixinFullResolution().transform(program);
-        new Printer(buffer).writeLibraryFile(
-            program.mainMethod.enclosingLibrary);
+        new Printer(buffer)
+            .writeLibraryFile(program.mainMethod.enclosingLibrary);
         String actual = buffer.toString();
         String expected =
             new File('${TESTCASE_DIR}/spec-mode/$name.baseline.txt')