Removing useless Win7 checks + standardize its use

device/power_save_blocker/power_save_blocker_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "device/power_save_blocker/power_save_blocker.h"
 
 #include <windows.h>
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/sequenced_task_runner.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/win/scoped_handle.h"
 #include "base/win/windows_version.h"
 
 namespace device {
 namespace {
 
-int g_blocker_count[2];
-
 HANDLE CreatePowerRequest(POWER_REQUEST_TYPE type,
                           const std::string& description) {
   if (type == PowerRequestExecutionRequired &&
-      base::win::GetVersion() < base::win::VERSION_WIN8) {
+      base::win::GetVersion() == base::win::VERSION_WIN7) {
     return INVALID_HANDLE_VALUE;
   }
 
   base::string16 wide_description = base::ASCIIToUTF16(description);
   REASON_CONTEXT context = {0};
   context.Version = POWER_REQUEST_CONTEXT_VERSION;
   context.Flags = POWER_REQUEST_CONTEXT_SIMPLE_STRING;
   context.Reason.SimpleReasonString =
       const_cast<wchar_t*>(wide_description.c_str());
 
   base::win::ScopedHandle handle(::PowerCreateRequest(&context));
   if (!handle.IsValid())
     return INVALID_HANDLE_VALUE;
 
   if (::PowerSetRequest(handle.Get(), type))
     return handle.Take();
 
   // Something went wrong.
   return INVALID_HANDLE_VALUE;
 }
 
 // Takes ownership of the |handle|.
 void DeletePowerRequest(POWER_REQUEST_TYPE type, HANDLE handle) {
   base::win::ScopedHandle request_handle(handle);
   if (!request_handle.IsValid())
     return;
 
   if (type == PowerRequestExecutionRequired &&
-      base::win::GetVersion() < base::win::VERSION_WIN8) {
+      base::win::GetVersion() == base::win::VERSION_WIN7) {
     return;
   }
 
   BOOL success = ::PowerClearRequest(request_handle.Get(), type);
   DCHECK(success);
 }
 
-void ApplySimpleBlock(PowerSaveBlocker::PowerSaveBlockerType type, int delta) {
-  g_blocker_count[type] += delta;
-  DCHECK_GE(g_blocker_count[type], 0);
-
-  if (g_blocker_count[type] > 1)
-    return;
-
-  DWORD this_flag = 0;
-  if (type == PowerSaveBlocker::kPowerSaveBlockPreventAppSuspension)
-    this_flag |= ES_SYSTEM_REQUIRED;
-  else
-    this_flag |= ES_DISPLAY_REQUIRED;
-
-  DCHECK(this_flag);
-
-  static DWORD flags = ES_CONTINUOUS;
-  if (!g_blocker_count[type])
-    flags &= ~this_flag;
-  else
-    flags |= this_flag;
-
-  SetThreadExecutionState(flags);
-}
-
 }  // namespace
 
 class PowerSaveBlocker::Delegate
     : public base::RefCountedThreadSafe<PowerSaveBlocker::Delegate> {
  public:
   Delegate(PowerSaveBlockerType type,
            const std::string& description,
            scoped_refptr<base::SequencedTaskRunner> ui_task_runner)
       : type_(type),
         description_(description),
@@ skipping 13 matching lines @@
   PowerSaveBlockerType type_;
   const std::string description_;
   base::win::ScopedHandle handle_;
   scoped_refptr<base::SequencedTaskRunner> ui_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(Delegate);
 };
 
 void PowerSaveBlocker::Delegate::ApplyBlock() {
   DCHECK(ui_task_runner_->RunsTasksInCurrentSequence());
-  if (base::win::GetVersion() < base::win::VERSION_WIN7)
-    return ApplySimpleBlock(type_, 1);
-
   handle_.Set(CreatePowerRequest(RequestType(), description_));
 }
 
 void PowerSaveBlocker::Delegate::RemoveBlock() {
   DCHECK(ui_task_runner_->RunsTasksInCurrentSequence());
-  if (base::win::GetVersion() < base::win::VERSION_WIN7)
-    return ApplySimpleBlock(type_, -1);
-
   DeletePowerRequest(RequestType(), handle_.Take());
 }
 
 POWER_REQUEST_TYPE PowerSaveBlocker::Delegate::RequestType() {
   if (type_ == kPowerSaveBlockPreventDisplaySleep)
     return PowerRequestDisplayRequired;
 
-  if (base::win::GetVersion() < base::win::VERSION_WIN8)
+  if (base::win::GetVersion() == base::win::VERSION_WIN7)
     return PowerRequestSystemRequired;
 
   return PowerRequestExecutionRequired;
 }
 
 PowerSaveBlocker::PowerSaveBlocker(
     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_));
 }
 
 PowerSaveBlocker::~PowerSaveBlocker() {
   ui_task_runner_->PostTask(FROM_HERE,
                             base::Bind(&Delegate::RemoveBlock, delegate_));
 }
 
 }  // namespace device