Typecheck const classes in the context of the constructor call.

tests/compiler/dart2js/compiler_helper.dart

Index: tests/compiler/dart2js/compiler_helper.dart
diff --git a/tests/compiler/dart2js/compiler_helper.dart b/tests/compiler/dart2js/compiler_helper.dart
index ce972e533609b29dd671629c258960b45f22c4c5..7f5baf229770354107dffee982c8895aef363b7b 100644
--- a/tests/compiler/dart2js/compiler_helper.dart
+++ b/tests/compiler/dart2js/compiler_helper.dart
@@ -96,6 +96,7 @@ MockCompiler compilerFor(String code, Uri uri,
                           bool disableInlining: true,
                           bool minify: false,
                           bool trustTypeAnnotations: false,
+                          bool enableTypeAssertions: false,
                           int expectedErrors,
                           int expectedWarnings,
                           api.CompilerOutputProvider outputProvider}) {
@@ -106,6 +107,7 @@ MockCompiler compilerFor(String code, Uri uri,
       disableInlining: disableInlining,
       enableMinification: minify,
       trustTypeAnnotations: trustTypeAnnotations,
+      enableTypeAssertions: enableTypeAssertions,
       expectedErrors: expectedErrors,
       expectedWarnings: expectedWarnings,
       outputProvider: outputProvider);