Reland of Pass SequencedTaskRunner to PowerSaveBlocker for ui/file ops

content/browser/power_save_blocker_win.cc

Index: content/browser/power_save_blocker_win.cc
diff --git a/content/browser/power_save_blocker_win.cc b/content/browser/power_save_blocker_win.cc
index ff78f1184f7cfef75b653b1b6704ba222b3e0d3d..e9650a5cc1f634eb827387d6828e81444e0c5fcb 100644
--- a/content/browser/power_save_blocker_win.cc
+++ b/content/browser/power_save_blocker_win.cc
@@ -2,16 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "content/browser/power_save_blocker_impl.h"
-
 #include <windows.h>
 
+#include "base/bind.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/win/scoped_handle.h"
 #include "base/win/windows_version.h"
-#include "content/public/browser/browser_thread.h"
+#include "content/browser/power_save_blocker_impl.h"
 
 namespace content {
 namespace {
@@ -88,8 +87,12 @@ void ApplySimpleBlock(PowerSaveBlocker::PowerSaveBlockerType type,
 class PowerSaveBlockerImpl::Delegate
     : public base::RefCountedThreadSafe<PowerSaveBlockerImpl::Delegate> {
  public:
-  Delegate(PowerSaveBlockerType type, const std::string& description)
-      : type_(type), description_(description) {}
+  Delegate(PowerSaveBlockerType type,
+           const std::string& description,
+           scoped_refptr<base::SequencedTaskRunner> ui_task_runner)
+      : type_(type),
+        description_(description),
+        ui_task_runner_(ui_task_runner) {}
 
   // Does the actual work to apply or remove the desired power save block.
   void ApplyBlock();
@@ -105,12 +108,13 @@ class PowerSaveBlockerImpl::Delegate
   PowerSaveBlockerType type_;
   const std::string description_;
   base::win::ScopedHandle handle_;
+  scoped_refptr<base::SequencedTaskRunner> ui_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(Delegate);
 };
 
 void PowerSaveBlockerImpl::Delegate::ApplyBlock() {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
   if (base::win::GetVersion() < base::win::VERSION_WIN7)
     return ApplySimpleBlock(type_, 1);
 
@@ -118,7 +122,7 @@ void PowerSaveBlockerImpl::Delegate::ApplyBlock() {
 }
 
 void PowerSaveBlockerImpl::Delegate::RemoveBlock() {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
   if (base::win::GetVersion() < base::win::VERSION_WIN7)
     return ApplySimpleBlock(type_, -1);
 
@@ -135,19 +139,22 @@ POWER_REQUEST_TYPE PowerSaveBlockerImpl::Delegate::RequestType() {
   return PowerRequestExecutionRequired;
 }
 
-PowerSaveBlockerImpl::PowerSaveBlockerImpl(PowerSaveBlockerType type,
-                                           Reason reason,
-                                           const std::string& description)
-    : delegate_(new Delegate(type, description)) {
-  BrowserThread::PostTask(
-      BrowserThread::UI, FROM_HERE,
-      base::Bind(&Delegate::ApplyBlock, delegate_));
+PowerSaveBlockerImpl::PowerSaveBlockerImpl(
+    PowerSaveBlockerType type,
+    Reason reason,
+    const std::string& description,
+    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
+    scoped_refptr<base::SingleThreadTaskRunner> blocking_task_runner)
+    : delegate_(new Delegate(type, description, ui_task_runner)),
+      ui_task_runner_(ui_task_runner),
+      blocking_task_runner_(blocking_task_runner) {
+  ui_task_runner_->PostTask(FROM_HERE,
+                            base::Bind(&Delegate::ApplyBlock, delegate_));
 }
 
 PowerSaveBlockerImpl::~PowerSaveBlockerImpl() {
-  BrowserThread::PostTask(
-      BrowserThread::UI, FROM_HERE,
-      base::Bind(&Delegate::RemoveBlock, delegate_));
+  ui_task_runner_->PostTask(FROM_HERE,
+                            base::Bind(&Delegate::RemoveBlock, delegate_));
 }
 
 }  // namespace content