cros: reset autoclick ring when SetEnabled(false)

Bug: 818364
Test: manual test
Change-Id: I2ca24231dd40478e3ad269d04bde02b613073fc3
Reviewed-on: https://chromium-review.googlesource.com/966490Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Commit-Queue: Qiang Xu <warx@google.com>
Cr-Commit-Position: refs/heads/master@{#544081}

ash/autoclick/autoclick_controller.cc

@@ -99,12 +99,12 @@ void AutoclickControllerImpl::SetEnabled(bool enabled) {
     return;
   enabled_ = enabled;
 
-  if (enabled_) {
+  if (enabled_)
     Shell::Get()->AddPreTargetHandler(this);
-    autoclick_controller_common_->CancelAutoclick();
-  } else {
+  else
     Shell::Get()->RemovePreTargetHandler(this);
-  }
+
+  autoclick_controller_common_->CancelAutoclick();
 }
 
 bool AutoclickControllerImpl::IsEnabled() const {