Add optional message to assert in Dart2js - continued

pkg/compiler/lib/src/compiler.dart

Index: pkg/compiler/lib/src/compiler.dart
diff --git a/pkg/compiler/lib/src/compiler.dart b/pkg/compiler/lib/src/compiler.dart
index f025a4190dce61e6a882e26a61cfa67be0abc4a2..6637af1038cb625d82883594839b5f393a2d54ab 100644
--- a/pkg/compiler/lib/src/compiler.dart
+++ b/pkg/compiler/lib/src/compiler.dart
@@ -191,6 +191,7 @@ abstract class Compiler implements DiagnosticListener {
   final bool dumpInfo;
   final bool useContentSecurityPolicy;
   final bool enableExperimentalMirrors;
+  final bool enableAssertMessage;
 
   /**
    * The maximum size of a concrete type before it widens to dynamic during
@@ -524,6 +525,7 @@ abstract class Compiler implements DiagnosticListener {
             this.fatalWarnings: false,
             bool hasIncrementalSupport: false,
             this.enableExperimentalMirrors: false,
+            this.enableAssertMessage: false,
             this.allowNativeExtensions: false,
             this.generateCodeWithCompileTimeErrors: false,
             this.testMode: false,