Update method count in mirrors_used_test.

tests/compiler/dart2js/mirrors_used_test.dart

Index: tests/compiler/dart2js/mirrors_used_test.dart
diff --git a/tests/compiler/dart2js/mirrors_used_test.dart b/tests/compiler/dart2js/mirrors_used_test.dart
index 39755167542fc32d78a337b23370429821a7e6ab..ededeaa2339b507ccb0394171ab6449141b945b8 100644
--- a/tests/compiler/dart2js/mirrors_used_test.dart
+++ b/tests/compiler/dart2js/mirrors_used_test.dart
@@ -63,7 +63,7 @@ void main() {
     // 2. Some code was refactored, and there are more methods.
     // Either situation could be problematic, but in situation 2, it is often
     // acceptable to increase [expectedMethodCount] a little.
-    int expectedMethodCount = 466;
+    int expectedMethodCount = 476;
     Expect.isTrue(
         generatedCode.length <= expectedMethodCount,
         'Too many compiled methods: '