Revert "Provide better messaging when user attempts to use non-secure http connection. (#26226)" (#26371)

This reverts commit d46b5b3 because it breaks g3 Fuchsia tests since g3 fuchsia doesn't have updated dart sdk.

Author: aam

lib/io/dart_io.cc

@@ -36,19 +36,6 @@ void DartIO::InitForIsolate(bool may_insecurely_connect_to_all_domains,
   Dart_Handle set_domain_network_policy_result = Dart_Invoke(
       embedder_config_type, ToDart("_setDomainPolicies"), 1, dart_args);
   FML_CHECK(!LogIfError(set_domain_network_policy_result));
-
-  Dart_Handle ui_lib = Dart_LookupLibrary(ToDart("dart:ui"));
-  Dart_Handle dart_validate_args[1];
-  dart_validate_args[0] = ToDart(may_insecurely_connect_to_all_domains);
-  Dart_Handle http_connection_hook_closure =
-      Dart_Invoke(ui_lib, ToDart("_getHttpConnectionHookClosure"),
-                  /*number_of_arguments=*/1, dart_validate_args);
-  FML_CHECK(!LogIfError(http_connection_hook_closure));
-  Dart_Handle http_lib = Dart_LookupLibrary(ToDart("dart:_http"));
-  FML_CHECK(!LogIfError(http_lib));
-  Dart_Handle set_http_connection_hook_result = Dart_SetField(
-      http_lib, ToDart("_httpConnectionHook"), http_connection_hook_closure);
-  FML_CHECK(!LogIfError(set_http_connection_hook_result));
 }
 
 }  // namespace flutter

lib/ui/hooks.dart

@@ -224,44 +224,3 @@ void _invoke3<A1, A2, A3>(void Function(A1 a1, A2 a2, A3 a3)? callback, Zone zon
     });
   }
 }
-
-bool _isLoopback(String host) {
-  if (host.isEmpty) {
-    return false;
-  }
-  if ('localhost' == host) {
-    return true;
-  }
-  try {
-    return InternetAddress(host).isLoopback;
-  } on ArgumentError {
-    return false;
-  }
-}
-
-/// Loopback connections are always allowed.
-/// Zone override with 'flutter.io.allow_http' takes first priority.
-/// If zone override is not provided, engine setting is checked.
-@pragma('vm:entry-point')
-// ignore: unused_element
-void Function(Uri) _getHttpConnectionHookClosure(bool mayInsecurelyConnectToAllDomains) {
-  return (Uri uri) {
-      if (_isLoopback(uri.host)) {
-        return;
-      }
-      final dynamic zoneOverride = Zone.current[#flutter.io.allow_http];
-      if (zoneOverride == true) {
-        return;
-      }
-      if (zoneOverride == false && uri.isScheme('http')) {
-        // Going to throw
-      } else if (mayInsecurelyConnectToAllDomains || uri.isScheme('https')) {
-        // In absence of zone override, if engine setting allows the connection
-        // or if connection is to `https`, allow the connection.
-        return;
-      }
-      throw UnsupportedError(
-        'Non-https connection "$uri" is not supported by the platform. '
-        'Refer to https://flutter.dev/docs/release/breaking-changes/network-policy-ios-android.');
-    };
-}

testing/dart/http_allow_http_connections_test.dart

@@ -13,7 +13,6 @@ import 'dart:collection' as collection;
 import 'dart:convert';
 import 'dart:developer' as developer;
 import 'dart:math' as math;
-import 'dart:io' show InternetAddress;
 import 'dart:nativewrappers';
 import 'dart:typed_data';
 

testing/dart/http_disallow_http_connections_test.dart

@@ -259,11 +259,6 @@ def RunDartTest(build_dir, test_packages, dart_file, verbose_dart_snapshot, mult
   if not enable_observatory:
     command_args.append('--disable-observatory')
 
-  dart_file_contents = open(dart_file, 'r')
-  custom_options = re.findall("// FlutterTesterOptions=(.*)", dart_file_contents.read())
-  dart_file_contents.close()
-  command_args.extend(custom_options)
-
   command_args += [
     '--use-test-fonts',
     kernel_file_output