Fix pre-existing HintCode.UNNECESSARY_TYPE_CHECK_TRUE (dart-lang/test_reflective_loader#36)

pkgs/test_reflective_loader/lib/test_reflective_loader.dart

diff --git a/pkgs/test_reflective_loader/lib/test_reflective_loader.dart b/pkgs/test_reflective_loader/lib/test_reflective_loader.dart
index 3528a43..fe78b9d 100644
--- a/pkgs/test_reflective_loader/lib/test_reflective_loader.dart
+++ b/pkgs/test_reflective_loader/lib/test_reflective_loader.dart
@@ -111,7 +111,7 @@
   classMirror.instanceMembers
       .forEach((Symbol symbol, MethodMirror memberMirror) {
     // we need only methods
-    if (memberMirror is! MethodMirror || !memberMirror.isRegularMethod) {
+    if (!memberMirror.isRegularMethod) {
       return;
     }
     // prepare information about the method