Revert of Reland RedirectNonUINonIOBrowserThreads to TaskScheduler by default on trunk

base/threading/thread_restrictions.h

Index: base/threading/thread_restrictions.h
diff --git a/base/threading/thread_restrictions.h b/base/threading/thread_restrictions.h
index e9f801778ea0edf81a316d7eeb0a9c436c3cadcd..1b51c46d91a11d53e11e703f21a7169b3c99a829 100644
--- a/base/threading/thread_restrictions.h
+++ b/base/threading/thread_restrictions.h
@@ -34,11 +34,9 @@
 namespace content {
 class BrowserGpuChannelHostFactory;
 class BrowserGpuMemoryBufferManager;
-class BrowserMainLoop;
 class BrowserShutdownProfileDumper;
 class BrowserSurfaceViewManager;
 class BrowserTestBase;
-class CategorizedWorkerPool;
 class NestedMessagePumpAndroid;
 class ScopedAllowWaitForAndroidLayoutTests;
 class ScopedAllowWaitForDebugURL;
@@ -47,6 +45,7 @@
 class SynchronousCompositorBrowserFilter;
 class SynchronousCompositorHost;
 class TextInputClientMac;
+class CategorizedWorkerPool;
 }  // namespace content
 namespace dbus {
 class Bus;
@@ -186,7 +185,6 @@
   friend class android_webview::AwFormDatabaseService;
   friend class android_webview::CookieManager;
   friend class base::StackSamplingProfiler;
-  friend class content::BrowserMainLoop;
   friend class content::BrowserShutdownProfileDumper;
   friend class content::BrowserSurfaceViewManager;
   friend class content::BrowserTestBase;