Use TaskScheduler instead of blocking pool in plugin_service_impl.cc.

content/browser/plugin_service_impl.cc

Index: content/browser/plugin_service_impl.cc
diff --git a/content/browser/plugin_service_impl.cc b/content/browser/plugin_service_impl.cc
index 480c659e0431c0b6c043c79eea3fa5567b4b8734..55d8a61c768ec9a53d9dac56c37672f56ddc21db 100644
--- a/content/browser/plugin_service_impl.cc
+++ b/content/browser/plugin_service_impl.cc
@@ -17,7 +17,7 @@
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/synchronization/waitable_event.h"
-#include "base/threading/sequenced_worker_pool.h"
+#include "base/task_scheduler/post_task.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
@@ -97,11 +97,11 @@ PluginServiceImpl::~PluginServiceImpl() {
 }
 
 void PluginServiceImpl::Init() {
-  plugin_list_task_runner_ =
-      BrowserThread::GetBlockingPool()
-          ->GetSequencedTaskRunnerWithShutdownBehavior(
-              base::SequencedWorkerPool::GetSequenceToken(),
-              base::SequencedWorkerPool::SKIP_ON_SHUTDOWN);
+  plugin_list_task_runner_ = base::CreateSequencedTaskRunnerWithTraits(
+      base::TaskTraits()
+          .MayBlock()
+          .WithPriority(base::TaskPriority::BACKGROUND)

[boliu, 2017/04/24 18:41:25]

probably should be user visible, I assume this is a request to populate the
plugins page, in which case that's a user waiting for the request

[fdoray, 2017/04/26 19:35:07]

Done.

+          .WithShutdownBehavior(base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN));
   PluginList::Singleton()->set_will_load_plugins_callback(
       base::Bind(&WillLoadPluginsCallback, &plugin_list_sequence_checker_));