Update tests to pass in web/production mode.

Change-Id: Ibea6022fcdd0eff53c6be9a5f7c0eeb0fbf20635
CoreLibraryReviewExempt: Updating tests to pass for web production backend.
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/343822
Reviewed-by: Mayank Patke <fishythefish@google.com>
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Commit-Queue: Nate Biggs <natebiggs@google.com>

tests/corelib/core_runtime_types_test.dart

@@ -85,6 +85,7 @@ class CoreRuntimeTypesTest {
   }
 
   static testOperatorErrors() {
+    if (dart2jsProductionMode) return; // Argument checks not performed.
     var objs = [
       1,
       '2',

tests/corelib/int_parse_radix_test.dart

@@ -6,10 +6,10 @@ import "package:expect/expect.dart";
 import "dart:math" show pow, log;
 
 void main() {
-  const String oneByteWhiteSpace = "\x09\x0a\x0b\x0c\x0d\x20"
-    "\x85" //# 01: ok
-      "\xa0";
-  const String whiteSpace = "$oneByteWhiteSpace\u1680"
+  final String oneByteWhiteSpace = webNumbers
+      ? "\x09\x0a\x0b\x0c\x0d\x20\xa0"
+      : "\x09\x0a\x0b\x0c\x0d\x20\x85\xa0";
+  final String whiteSpace = "$oneByteWhiteSpace\u1680"
       "\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a"
       "\u2028\u2029\u202f\u205f\u3000\ufeff";
 
@@ -92,8 +92,8 @@ void main() {
   Expect.equals(1, int.parse("+1", radix: 2));
 
   void testFails(String source, int radix) {
-   Expect.throwsFormatException(
-      () => int.parse(source, radix: radix), "$source/$radix");
+    Expect.throwsFormatException(
+        () => int.parse(source, radix: radix), "$source/$radix");
     Expect.equals(-999, int.tryParse(source, radix: radix) ?? -999);
   }
 
@@ -113,8 +113,7 @@ void main() {
 
   testBadArguments(String source, int radix) {
     // If the types match, it should be an ArgumentError of some sort.
-    Expect.throwsArgumentError(
-        () => int.parse(source, radix: radix));
+    Expect.throwsArgumentError(() => int.parse(source, radix: radix));
   }
 
   testBadArguments("0", -1);

tests/corelib/list_removeat_test.dart

@@ -25,10 +25,14 @@ void testModifiableList(l1) {
   // Index must be integer and in range.
   Expect.throwsRangeError(() => l1.removeAt(-1), "negative");
   Expect.throwsRangeError(() => l1.removeAt(5), "too large");
-  Expect.throws(() => l1.removeAt(null),
-      // With sound null safety a TypeError is thrown.
-      // Without sound null safety an ArgumentError is thrown.
-      (e) => e is TypeError || e is ArgumentError, "is null");
+  if (!dart2jsProductionMode) {
+    Expect.throws(
+        () => l1.removeAt(null),
+        // With sound null safety a TypeError is thrown.
+        // Without sound null safety an ArgumentError is thrown.
+        (e) => e is TypeError || e is ArgumentError,
+        "is null");
+  }
 
   Expect.equals(2, l1.removeAt(2), "l1-remove2");
   Expect.equals(1, l1[1], "l1-1[1]");