Added UMA metrics for display settings UI in the status area.

ash/system/chromeos/tray_display.cc

Index: ash/system/chromeos/tray_display.cc
diff --git a/ash/system/chromeos/tray_display.cc b/ash/system/chromeos/tray_display.cc
index 8bf2f602d99be57c9115f5c8d59962eff7ade0ca..67e8443b740dc9c5edcac4932b4a2f00d8c6fda2 100644
--- a/ash/system/chromeos/tray_display.cc
+++ b/ash/system/chromeos/tray_display.cc
@@ -8,6 +8,7 @@
 #include <utility>
 #include <vector>
 
+#include "ash/common/metrics/user_metrics_action.h"
 #include "ash/common/system/chromeos/devicetype_utils.h"
 #include "ash/common/system/system_notifier.h"
 #include "ash/common/system/tray/actionable_view.h"
@@ -112,7 +113,7 @@ base::string16 GetAllDisplayInfo() {
   return base::JoinString(lines, base::ASCIIToUTF16("\n"));
 }
 
-void OpenSettings() {
+void OpenSettings(UserMetricsAction action) {

[tdanderson, 2016/07/07 21:41:39]

nit: Add a brief explanation to the documentation of OpenSettings() in the .h to
explain the new parameter

[bruthig, 2016/07/08 17:12:51]

This got reworked a little bit.

   // switch is intentionally introduced without default, to cause an error when
   // a new type of login status is introduced.
   switch (WmShell::Get()->system_tray_delegate()->GetUserLoginStatus()) {
@@ -130,6 +131,8 @@ void OpenSettings() {
       if (delegate->ShouldShowSettings())
         delegate->ShowDisplaySettings();
   }
+
+  WmShell::Get()->RecordUserMetricsAction(action);
 }
 
 }  // namespace
@@ -280,7 +283,7 @@ class DisplayView : public ActionableView {
 
   // Overridden from ActionableView.
   bool PerformAction(const ui::Event& event) override {
-    OpenSettings();
+    OpenSettings(UMA_STATUS_AREA_DISPLAY_DEFAULT_CLICKED);
     return true;
   }
 
@@ -404,8 +407,8 @@ void TrayDisplay::CreateOrUpdateNotification(
       message_center::NotifierId(message_center::NotifierId::SYSTEM_COMPONENT,
                                  system_notifier::kNotifierDisplay),
       message_center::RichNotificationData(),
-      new message_center::HandleNotificationClickedDelegate(
-          base::Bind(&OpenSettings))));
+      new message_center::HandleNotificationClickedDelegate(base::Bind(
+          &OpenSettings, UMA_STATUS_AREA_DISPLAY_NOTIFICATION_CLICKED))));
 
   message_center::MessageCenter::Get()->AddNotification(
       std::move(notification));