UMA for pin unlock success/failure.

chrome/browser/chromeos/login/lock/screen_locker.cc

Index: chrome/browser/chromeos/login/lock/screen_locker.cc
diff --git a/chrome/browser/chromeos/login/lock/screen_locker.cc b/chrome/browser/chromeos/login/lock/screen_locker.cc
index bffe739b0a78a3888c2b5780634e16f315b77887..c4902a2fc717027f052fcf5a5dfd4a1af9d9bb63 100644
--- a/chrome/browser/chromeos/login/lock/screen_locker.cc
+++ b/chrome/browser/chromeos/login/lock/screen_locker.cc
@@ -140,6 +140,7 @@ ScreenLocker::ScreenLocker(const user_manager::UserList& users)
       start_time_(base::Time::Now()),
       auth_status_consumer_(NULL),
       incorrect_passwords_count_(0),
+      is_pin_attempt_(false),

[jdufault, 2016/08/12 21:57:33]

Since you're already modifying this, please move all of these initializations
(where possible) to the header. Replace the NULL with nullptr.

[sammiequon, 2016/08/16 17:29:09]

Done.

       weak_factory_(this) {
   DCHECK(!screen_locker_);
   screen_locker_ = this;
@@ -189,6 +190,16 @@ void ScreenLocker::OnAuthFailure(const AuthFailure& error) {
     UMA_HISTOGRAM_TIMES("ScreenLocker.AuthenticationFailureTime", delta);
   }
 
+  if (is_pin_attempt_) {
+    UMA_HISTOGRAM_ENUMERATION("ScreenLocker.AuthenticationFailure",
+                              UnlockFailure::AUTH_FAILURE_PIN,

[jdufault, 2016/08/12 21:57:33]

Can we replace this with

UMA(..., is_pin_attempt_ ? UnlockFailure::AUTH_FAILURE_PIN :
UnlockFailure::AUTH_FAILURE_PASSWORD, ...)

[sammiequon, 2016/08/16 17:29:09]

Done.

+                              UnlockFailure::AUTH_FAILURE_COUNT);
+  } else {
+    UMA_HISTOGRAM_ENUMERATION("ScreenLocker.AuthenticationFailure",
+                              UnlockFailure::AUTH_FAILURE_PASSWORD,
+                              UnlockFailure::AUTH_FAILURE_COUNT);
+  }
+
   EnableInput();
   // Don't enable signout button here as we're showing
   // MessageBubble.
@@ -213,6 +224,16 @@ void ScreenLocker::OnAuthSuccess(const UserContext& user_context) {
     UMA_HISTOGRAM_TIMES("ScreenLocker.AuthenticationSuccessTime", delta);
   }
 
+  if (is_pin_attempt_) {
+    UMA_HISTOGRAM_ENUMERATION("ScreenLocker.AuthenticationSuccess",
+                              UnlockSuccess::AUTH_SUCCESS_PIN,
+                              UnlockSuccess::AUTH_SUCCESS_COUNT);

[jdufault, 2016/08/12 21:57:33]

See above UMA comment

[sammiequon, 2016/08/16 17:29:09]

Done.

+  } else {
+    UMA_HISTOGRAM_ENUMERATION("ScreenLocker.AuthenticationSuccess",
+                              UnlockSuccess::AUTH_SUCCESS_PASSWORD,
+                              UnlockSuccess::AUTH_SUCCESS_COUNT);
+  }
+
   const user_manager::User* user =
       user_manager::UserManager::Get()->FindUser(user_context.GetAccountId());
   if (user) {
@@ -283,6 +304,7 @@ void ScreenLocker::Authenticate(const UserContext& user_context) {
   authentication_start_time_ = base::Time::Now();
   delegate_->SetInputEnabled(false);
   delegate_->OnAuthenticate();
+  is_pin_attempt_ = user_context.IsUsingPin();
 
   const user_manager::User* user = FindUnlockUser(user_context.GetAccountId());
   if (user) {
@@ -293,7 +315,7 @@ void ScreenLocker::Authenticate(const UserContext& user_context) {
     // otherwise we will timeout PIN if the user enters their account password
     // incorrectly more than a few times.
     int dummy_value;
-    if (base::StringToInt(pin, &dummy_value)) {
+    if (is_pin_attempt_ && base::StringToInt(pin, &dummy_value)) {
       chromeos::PinStorage* pin_storage =
           chromeos::PinStorageFactory::GetForUser(user);
       if (pin_storage && pin_storage->TryAuthenticatePin(pin)) {