UMA metrics added for HID detection dialog.

chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.cc

Index: chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.cc
diff --git a/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.cc
index d7077e0c3fa61d9dd5bae19f2debf3f1aeb69ba4..4a6c27197d45b9ad226754263d6b339e9f62eb15 100644
--- a/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.cc
@@ -7,6 +7,7 @@
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
+#include "base/metrics/user_metrics.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
@@ -62,7 +63,7 @@ HIDDetectionScreenHandler::HIDDetectionScreenHandler()
       mouse_is_pairing_(false),
       keyboard_is_pairing_(false),
       switch_on_adapter_when_ready_(false),
-      skip_screen_if_devices_present_(true),
+      first_time_screen_show_(true),
       weak_ptr_factory_(this) {
 }
 
@@ -95,7 +96,7 @@ void HIDDetectionScreenHandler::Show() {
     return;
   }
   input_service_proxy_.AddObserver(this);
-  skip_screen_if_devices_present_ = true;
+  first_time_screen_show_ = true;
   UpdateDevices();
   ShowScreen(OobeUI::kScreenHIDDetection, NULL);
 }
@@ -369,14 +370,18 @@ void HIDDetectionScreenHandler::OnGetInputDevicesList(
       SendKeyboardDeviceNotification(NULL);
     }
   }
-  // Skip screen if both devices are present and skip was requested.
-  if (!pointing_device_id_.empty() &&
-      !keyboard_device_id_.empty() &&
-      skip_screen_if_devices_present_) {
-    HandleOnContinue();
+
+  if (first_time_screen_show_) {
+    // Skip screen if both devices are present and it's first show.
+    if (!pointing_device_id_.empty() && !keyboard_device_id_.empty()) {
+      HandleOnContinue();
+    } else {
+      base::RecordAction(
+          base::UserMetricsAction("OOBE.HIDDetectionDialogShown"));

[ygorshenin1, 2014/05/08 11:50:08]

Consider to use HISTOGRAM_BOOLEAN.

[merkulova, 2014/05/12 10:22:59]

Done.

+    }
   }
-  // Skip requested only once on dialog show.
-  skip_screen_if_devices_present_ = false;
+
+  first_time_screen_show_ = false;
   if ((pointing_device_id_.empty() || keyboard_device_id_.empty()) &&
       adapter_) {
     if (!adapter_->IsPresent()) {