Add Browser Task Scheduler Flags to iOS

ios/chrome/browser/about_flags.mm

Index: ios/chrome/browser/about_flags.mm
diff --git a/ios/chrome/browser/about_flags.mm b/ios/chrome/browser/about_flags.mm
index 515fc1b2f51c990c3b80e74c1e1e9b49d6f66da2..c18509148853a1a3470e2d57478f9177f73bfe77 100644
--- a/ios/chrome/browser/about_flags.mm
+++ b/ios/chrome/browser/about_flags.mm
@@ -19,6 +19,7 @@
 #include "base/strings/stringprintf.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/sys_info.h"
+#include "base/task_scheduler/switches.h"
 #include "components/dom_distiller/core/dom_distiller_switches.h"
 #include "components/flags_ui/feature_entry.h"
 #include "components/flags_ui/feature_entry_macros.h"
@@ -57,6 +58,10 @@ const flags_ui::FeatureEntry kFeatureEntries[] = {
      IDS_IOS_FLAGS_PHYSICAL_WEB_DESCRIPTION, flags_ui::kOsIos,
      ENABLE_DISABLE_VALUE_TYPE(switches::kEnableIOSPhysicalWeb,
                                switches::kDisableIOSPhysicalWeb)},
+    {"browser-task-scheduler", IDS_IOS_FLAGS_BROWSER_TASK_SCHEDULER_NAME,
+     IDS_IOS_FLAGS_BROWSER_TASK_SCHEDULER_DESCRIPTION, flags_ui::kOsIos,
+     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableBrowserTaskScheduler,
+                               switches::kDisableBrowserTaskScheduler)},
 };
 
 // Add all switches from experimental flags to |command_line|.