Use task runner in version_updater_win.cc.

chrome/browser/google/google_update_win.cc

Index: chrome/browser/google/google_update_win.cc
diff --git a/chrome/browser/google/google_update_win.cc b/chrome/browser/google/google_update_win.cc
index 48df1755ab31e9ed8ab1c96650110454273e7d3e..6bed7ee8343ac3b54f32114c04ada9e41a2a2890 100644
--- a/chrome/browser/google/google_update_win.cc
+++ b/chrome/browser/google/google_update_win.cc
@@ -27,6 +27,8 @@
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/task_scheduler/post_task.h"
+#include "base/task_scheduler/task_traits.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "base/version.h"
@@ -205,10 +207,9 @@ HRESULT CreateGoogleUpdate3WebClass(
 // Google Update on another.
 class UpdateCheckDriver {
  public:
-  // Runs an update check on |task_runner|, invoking methods of |delegate| on
-  // the caller's thread to report progress and final results.
+  // Runs an update check, invoking methods of |delegate| on the caller's thread
+  // to report progress and final results.
   static void RunUpdateCheck(
-      scoped_refptr<base::SingleThreadTaskRunner> task_runner,
       const std::string& locale,
       bool install_update_if_possible,
       gfx::AcceleratedWidget elevation_window,
@@ -218,7 +219,6 @@ class UpdateCheckDriver {
   friend class base::DeleteHelper<UpdateCheckDriver>;
 
   UpdateCheckDriver(
-      scoped_refptr<base::SingleThreadTaskRunner> task_runner,
       const std::string& locale,
       bool install_update_if_possible,
       gfx::AcceleratedWidget elevation_window,
@@ -369,7 +369,6 @@ UpdateCheckDriver* UpdateCheckDriver::driver_ = nullptr;
 
 // static
 void UpdateCheckDriver::RunUpdateCheck(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     const std::string& locale,
     bool install_update_if_possible,
     gfx::AcceleratedWidget elevation_window,
@@ -379,26 +378,24 @@ void UpdateCheckDriver::RunUpdateCheck(
   if (!driver_) {
     // The driver is owned by itself, and will self-destruct when its work is
     // done.
-    driver_ =
-        new UpdateCheckDriver(task_runner, locale, install_update_if_possible,
-                              elevation_window, delegate);
-    task_runner->PostTask(FROM_HERE,
-                          base::Bind(&UpdateCheckDriver::BeginUpdateCheck,
-                                     base::Unretained(driver_)));
+    driver_ = new UpdateCheckDriver(locale, install_update_if_possible,
+                                    elevation_window, delegate);
+    driver_->task_runner_->PostTask(
+        FROM_HERE, base::Bind(&UpdateCheckDriver::BeginUpdateCheck,
+                              base::Unretained(driver_)));
   } else {
-    DCHECK_EQ(driver_->task_runner_, task_runner);
     driver_->AddDelegate(delegate);
   }
 }
 
 // Runs on the caller's thread.
 UpdateCheckDriver::UpdateCheckDriver(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     const std::string& locale,
     bool install_update_if_possible,
     gfx::AcceleratedWidget elevation_window,
     const base::WeakPtr<UpdateCheckDelegate>& delegate)
-    : task_runner_(std::move(task_runner)),
+    : task_runner_(base::CreateSingleThreadTaskRunnerWithTraits(

[gab, 2017/07/17 17:14:40]

Does CreateSequencedTaskRunnerWithTraits() work?

https://chromium.googlesource.com/chromium/src/+/master/docs/threading_and_ta...

[calamity, 2017/07/19 09:03:38]

Seems to.

+          {base::MayBlock(), base::TaskPriority::USER_VISIBLE})),
       result_runner_(base::ThreadTaskRunnerHandle::Get()),
       locale_(locale),
       install_update_if_possible_(install_update_if_possible),
@@ -867,13 +864,11 @@ void UpdateCheckDriver::OnUpgradeError(GoogleUpdateErrorCode error_code,
 // Globals ---------------------------------------------------------------------
 
 void BeginUpdateCheck(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     const std::string& locale,
     bool install_update_if_possible,
     gfx::AcceleratedWidget elevation_window,
     const base::WeakPtr<UpdateCheckDelegate>& delegate) {
-  UpdateCheckDriver::RunUpdateCheck(std::move(task_runner), locale,
-                                    install_update_if_possible,
+  UpdateCheckDriver::RunUpdateCheck(locale, install_update_if_possible,
                                     elevation_window, delegate);
 }