Fix nits after refactoring WakeLockServiceImpl.

device/wake_lock/wake_lock_service_impl.cc

 // Copyright 2015 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/wake_lock/wake_lock_service_impl.h"
 
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 
@@ skipping 45 matching lines @@
 }
 
 void WakeLockServiceImpl::CancelWakeLock() {
   DCHECK(main_task_runner_->RunsTasksOnCurrentThread());
   DCHECK(binding_set_.dispatch_context());
 
   if (!(*binding_set_.dispatch_context()))
     return;
 
   *binding_set_.dispatch_context() = false;
-  if (num_lock_requests_ > 0) {
-    num_lock_requests_--;
-    UpdateWakeLock();
-  }
+  DCHECK(num_lock_requests_ > 0);

[blundell, 2017/05/09 16:05:11]

tiny nit: I would order this above line 65 from a readability POV, as it's kind
of a precondition of going into this code block.

[ke.he, 2017/05/10 02:42:14]

Done.

+  num_lock_requests_--;
+  UpdateWakeLock();
 }
 
 void WakeLockServiceImpl::HasWakeLockForTests(
     const HasWakeLockForTestsCallback& callback) {
   callback.Run(!!wake_lock_);
 }
 void WakeLockServiceImpl::UpdateWakeLock() {
   DCHECK(num_lock_requests_ >= 0);
 
   if (num_lock_requests_) {
@@ skipping 25 matching lines @@
     wake_lock_.get()->InitDisplaySleepBlocker(native_view);
 #endif
 }
 
 void WakeLockServiceImpl::RemoveWakeLock() {
   DCHECK(wake_lock_);
   wake_lock_.reset();
 }
 
 void WakeLockServiceImpl::OnConnectionError() {
-  DCHECK(binding_set_.dispatch_context());
-
   // If the error-happening client's wakelock is in outstanding status,

[blundell, 2017/05/09 16:05:11]

tiny nit: "the error-happening client's wakelock is in outstanding status" ->
"this client has an outstanding wake lock request"

[ke.he, 2017/05/10 02:42:14]

Thanks:)
Done.

   // decrease the num_lock_requests and call UpdateWakeLock().
   if (*binding_set_.dispatch_context() && num_lock_requests_ > 0) {
     num_lock_requests_--;
     UpdateWakeLock();
   }
 
-  // If |binding_set_| is empty, WakeLockServiceImpl should delele itself.
   if (binding_set_.empty())
     base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, this);
 }
 
 }  // namespace device