Add UKM metrics for password submission indicator.

The CL is created in response to https://chromium-review.googlesource.com/c/chromium/src/+/1057235
SubmissionIndicatorEvent is already recorded via UMA. It indicates the event that made the password manager believe that there was a submission. The UKM is to be recorded only when a password is saved. It means that the submission detectioln was probably correct.

Bug: 842643
Change-Id: Ic381ee93de7459d7d942a9ee1b27d43e39095fc7
Reviewed-on: https://chromium-review.googlesource.com/1060034Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Reviewed-by: Dominic Battré <battre@chromium.org>
Commit-Queue: Vasilii Sukhanov <vasilii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#559236}

components/password_manager/core/browser/password_form_manager.cc

@@ -386,6 +386,8 @@ void PasswordFormManager::Save() {
 
   metrics_util::LogPasswordAcceptedSaveUpdateSubmissionIndicatorEvent(
       submitted_form_->submission_event);
+  metrics_recorder_->SetSubmissionIndicatorEvent(
+      submitted_form_->submission_event);
 
   if ((user_action_ == UserAction::kNone) &&
       DidPreferenceChange(best_matches_, pending_credentials_.username_value)) {
@@ -421,6 +423,8 @@ void PasswordFormManager::Update(
     const autofill::PasswordForm& credentials_to_update) {
   metrics_util::LogPasswordAcceptedSaveUpdateSubmissionIndicatorEvent(
       submitted_form_->submission_event);
+  metrics_recorder_->SetSubmissionIndicatorEvent(
+      submitted_form_->submission_event);
   if (observed_form_.IsPossibleChangePasswordForm()) {
     FormStructure form_structure(credentials_to_update.form_data);
     UploadPasswordVote(observed_form_, autofill::NEW_PASSWORD,

components/password_manager/core/browser/password_form_metrics_recorder.cc

@@ -200,6 +200,11 @@ void PasswordFormMetricsRecorder::SetSubmittedFormType(
   submitted_form_type_ = form_type;
 }
 
+void PasswordFormMetricsRecorder::SetSubmissionIndicatorEvent(
+    autofill::PasswordForm::SubmissionIndicatorEvent event) {
+  ukm_entry_builder_.SetSubmission_Indicator(static_cast<int>(event));
+}
+
 int PasswordFormMetricsRecorder::GetActionsTakenNew() const {
   // Merge kManagerActionNone and kManagerActionBlacklisted_Obsolete. This
   // lowers the number of histogram buckets used by 33%.

components/password_manager/core/browser/password_form_metrics_recorder.h

@@ -194,6 +194,11 @@ class PasswordFormMetricsRecorder
   // Call this once the submitted form type has been determined.
   void SetSubmittedFormType(SubmittedFormType form_type);
 
+  // Call this when a password is saved to indicate which path led to
+  // submission.
+  void SetSubmissionIndicatorEvent(
+      autofill::PasswordForm::SubmissionIndicatorEvent event);
+
   // Records all histograms in the PasswordManager.SuppressedAccount.* family.
   // Takes the FormFetcher intance which owns the login data from PasswordStore.
   // |pending_credentials| stores credentials when the form was submitted but

tools/metrics/ukm/ukm.xml

@@ -2197,6 +2197,14 @@ be describing additional metrics about the same event.
       correspond to the enum PasswordFormMetricsRecorder::BubbleTrigger.
     </summary>
   </metric>
+  <metric name="Submission.Indicator">
+    <summary>
+      Records the event that led the password manager to believe the submission
+      was successful. Metrics is recorded only when the password is saved.
+      Recorded values correspond to the enum
+      autofill::PasswordForm::SubmissionIndicatorEvent.
+    </summary>
+  </metric>
   <metric name="Submission.Observed">
     <summary>
       Records whether a submission of a password form has been observered. The