Fix nits after refactoring WakeLockServiceImpl.

device/wake_lock/wake_lock_service_impl.cc

Index: device/wake_lock/wake_lock_service_impl.cc
diff --git a/device/wake_lock/wake_lock_service_impl.cc b/device/wake_lock/wake_lock_service_impl.cc
index 6e1571806cb7d185afabe6c7f05e679defa165a7..038e5f04d075470a3eed597f728ecce03e798abc 100644
--- a/device/wake_lock/wake_lock_service_impl.cc
+++ b/device/wake_lock/wake_lock_service_impl.cc
@@ -63,10 +63,9 @@ void WakeLockServiceImpl::CancelWakeLock() {
     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(
@@ -112,8 +111,6 @@ void WakeLockServiceImpl::RemoveWakeLock() {
 }
 
 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) {
@@ -121,7 +118,6 @@ void WakeLockServiceImpl::OnConnectionError() {
     UpdateWakeLock();
   }
 
-  // If |binding_set_| is empty, WakeLockServiceImpl should delele itself.
   if (binding_set_.empty())
     base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, this);
 }