UMA stats for stylus usage

chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.h

Index: chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.h
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.h b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.h
index 61a76aaa4b121608682bea2e502b59921b1f6dfe..4bee7b15185d5b7edd73da2b2c65bb13e2a68c53 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.h
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_impl.h
@@ -21,6 +21,7 @@
 #include "chrome/browser/ui/ash/app_sync_ui_state_observer.h"
 #include "chrome/browser/ui/ash/launcher/chrome_launcher_controller.h"
 #include "chrome/browser/ui/ash/launcher/launcher_app_updater.h"
+#include "chrome/browser/ui/ash/metrics/stylus_metrics_recorder.h"

[sky, 2016/09/13 00:03:25]

Only include this if on chromeos (to match your ifdef below).

[xiaoyinh(OOO Sep 11-29), 2016/09/16 18:41:16]

Done.

 #include "components/prefs/pref_change_registrar.h"
 #include "ui/aura/window_observer.h"
 
@@ -368,6 +369,11 @@ class ChromeLauncherControllerImpl
   typedef std::map<std::string, RunningAppListIds> RunningAppListIdMap;
   RunningAppListIdMap last_used_running_application_order_;
 
+#if defined(OS_CHROMEOS)
+  // Record stylus metrics for down event.
+  std::unique_ptr<chromeos::StylusMetricsRecorder> stylus_metrics_recorder_;
+#endif
+
   base::WeakPtrFactory<ChromeLauncherControllerImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeLauncherControllerImpl);