[js_runtime] Safe-print records in Error messages

The js_runtime implementation of `Error.safeToString` now understands
Records.

`ArgumentError.value((1, 2))` now prints as

    Invalid argument: Record (1, 2)

instead of the old way:

    Invalid argument: Instance of '_Record_2'

I don't think `Record` is necessary, but this is consistent with the
VM error messages.

Bug: 49718
Change-Id: Icde50f12a3956aa8954ee083307c1e5b13871e41
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/290349
Reviewed-by: Mayank Patke <fishythefish@google.com>
Commit-Queue: Stephen Adams <sra@google.com>

sdk/lib/_internal/js_runtime/lib/core_patch.dart

@@ -220,14 +220,12 @@ class double {
 class Error {
   @patch
   static String _objectToString(Object object) {
-    // Closures all have useful and safe toString methods.
-    if (object is Closure) return object.toString();
-    return Primitives.objectToHumanReadableString(object);
+    return Primitives.safeToString(object);
   }
 
   @patch
   static String _stringToSafeString(String string) {
-    return jsonEncodeNative(string);
+    return Primitives.stringSafeToString(string);
   }
 
   @patch

sdk/lib/_internal/js_runtime/lib/js_helper.dart

@@ -483,6 +483,28 @@ class Primitives {
     return "Instance of '$name'";
   }
 
+  static String stringSafeToString(String string) {
+    return jsonEncodeNative(string);
+  }
+
+  static String safeToString(Object? object) {
+    if (object == null || object is num || object is bool) {
+      return object.toString();
+    }
+    if (object is String) {
+      return stringSafeToString(object);
+    }
+    // Closures all have useful and safe toString methods.
+    if (object is Closure) {
+      return object.toString();
+    }
+    if (object is _Record) {
+      return object._toString(true);
+    }
+
+    return Primitives.objectToHumanReadableString(object);
+  }
+
   static int dateNow() => JS('int', r'Date.now()');
 
   static void initTicker() {
@@ -1878,11 +1900,16 @@ int getLength(var array) {
 invokeClosure(Function closure, int numberOfArguments, var arg1, var arg2,
     var arg3, var arg4) {
   switch (numberOfArguments) {
-    case 0: return closure();
-    case 1: return closure(arg1);
-    case 2: return closure(arg1, arg2);
-    case 3: return closure(arg1, arg2, arg3);
-    case 4: return closure(arg1, arg2, arg3, arg4);
+    case 0:
+      return closure();
+    case 1:
+      return closure(arg1);
+    case 2:
+      return closure(arg1, arg2);
+    case 3:
+      return closure(arg1, arg2, arg3);
+    case 4:
+      return closure(arg1, arg2, arg3, arg4);
   }
   throw new Exception('Unsupported number of arguments for wrapped closure');
 }

sdk/lib/_internal/js_runtime/lib/records.dart

@@ -29,12 +29,15 @@ abstract final class _Record implements Record {
   }
 
   @override
-  String toString() {
+  String toString() => _toString(false);
+
+  String _toString(bool safe) {
     final keys = _fieldKeys();
     final values = _getFieldValues();
     assert(keys.length == values.length);
     final sb = StringBuffer();
     String separator = '';
+    if (safe) sb.write('Record ');
     sb.write('(');
     for (int i = 0; i < keys.length; i++) {
       sb.write(separator);
@@ -43,7 +46,12 @@ abstract final class _Record implements Record {
         sb.write(key);
         sb.write(': ');
       }
-      sb.write(values[i]);
+      final value = values[i];
+      if (safe) {
+        sb.write(Primitives.safeToString(value));
+      } else {
+        sb.write(value);
+      }
       separator = ', ';
     }
     sb.write(')');