Revert of Disallow posting tasks to SequencedWorkerPools by default.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index f656eadca32efa2b3bca62d08834adaf94f94b08..d569350255fc98759f0de7ce89f7cd3374f98c42 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -30,7 +30,6 @@
 #include "base/strings/string_split.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
-#include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/simple_thread.h"
 #include "base/threading/thread_local.h"
 #include "base/threading/thread_restrictions.h"
@@ -903,13 +902,6 @@
   is_renderer_suspended_ = false;
 
   base::MemoryCoordinatorClientRegistry::GetInstance()->Register(this);
-
-  // If this renderer doesn't run inside the browser process, enable
-  // SequencedWorkerPool. Otherwise, it should already have been enabled.
-  // TODO(fdoray): Remove this once the SequencedWorkerPool to TaskScheduler
-  // redirection experiment concludes https://crbug.com/622400.
-  if (!command_line.HasSwitch(switches::kSingleProcess))
-    base::SequencedWorkerPool::EnableForProcess();
 }
 
 RenderThreadImpl::~RenderThreadImpl() {