[Merge-112][Passwords] Additional metric for OTP regexes

The metric measures how often an OTP regexs detects anything. It will be
used to compare coverage between new and old regexes.

(cherry picked from commit 51d4c63)

Bug: 1382805
Change-Id: I86a3474754d7a5bc22a79205a60d8d7d5d3710f5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4290992
Reviewed-by: Mohamed Amir Yosef <mamir@chromium.org>
Commit-Queue: Maxim Kolosovskiy <kolos@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#1109635}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4293107
Cr-Commit-Position: refs/branch-heads/5615@{#33}
Cr-Branched-From: 9c6408e-refs/heads/main@{#1109224}

components/password_manager/core/browser/form_parsing/form_parser.cc

@@ -124,15 +124,22 @@ bool StringMatchesHiddenValue(const std::u16string& str) {
 // The suspicion is based on server-side provided hints and on checking the
 // field's id and name for hinting towards a CVC code, Social Security
 // Number or one-time password.
-bool IsNotPasswordField(const ProcessedField& field) {
-  return field.server_hints_not_password ||
-         field.autocomplete_flag == AutocompleteFlag::kNonPassword ||
-         StringMatchesCVC(field.field->name_attribute) ||
-         StringMatchesCVC(field.field->id_attribute) ||
-         StringMatchesSSN(field.field->name_attribute) ||
-         StringMatchesSSN(field.field->id_attribute) ||
-         StringMatchesOTP(field.field->name_attribute) ||
-         StringMatchesOTP(field.field->id_attribute);
+bool IsNotPasswordField(const ProcessedField& field,
+                        bool* otp_field_detected_with_regex = nullptr) {
+  if (field.server_hints_not_password ||
+      field.autocomplete_flag == AutocompleteFlag::kNonPassword ||
+      StringMatchesCVC(field.field->name_attribute) ||
+      StringMatchesCVC(field.field->id_attribute) ||
+      StringMatchesSSN(field.field->name_attribute) ||
+      StringMatchesSSN(field.field->id_attribute)) {
+    return true;
+  }
+  bool is_otp_field = StringMatchesOTP(field.field->name_attribute) ||
+                      StringMatchesOTP(field.field->id_attribute);
+  if (otp_field_detected_with_regex) {
+    *otp_field_detected_with_regex |= is_otp_field;
+  }
+  return is_otp_field;
 }
 
 // Returns true if the |field| is suspected to be not the username field.
@@ -769,10 +776,18 @@ void ParseUsingBaseHeuristics(
   if (!found_fields->HasPasswords()) {
     // What is the best interactability among passwords?
     Interactability password_max = Interactability::kUnlikely;
+    // TODO(crbug.com/1382805): The variable is used only for metrics for the
+    // new OTP regex launch. Remove the variable after the launch.
+    bool otp_field_detected_with_regex = false;
     for (const ProcessedField& processed_field : processed_fields) {
-      if (processed_field.is_password && !IsNotPasswordField(processed_field))
+      if (processed_field.is_password &&
+          !IsNotPasswordField(processed_field,
+                              &otp_field_detected_with_regex)) {
         password_max = std::max(password_max, processed_field.interactability);
+      }
     }
+    base::UmaHistogramBoolean("PasswordManager.ParserDetectedOtpFieldWithRegex",
+                              otp_field_detected_with_regex);
 
     // Try to find password elements (current, new, confirmation) among those
     // with best interactability.

components/password_manager/core/browser/form_parsing/form_parser_unittest.cc

@@ -1970,6 +1970,24 @@ TEST(FormParserTest, SSN_and_OTP) {
   }
 }
 
+TEST(FormParserTest, OtpRegexMetric) {
+  base::HistogramTester histogram_tester;
+  CheckTestData({{
+      .fields =
+          {
+              {.role = ElementRole::USERNAME, .form_control_type = "text"},
+              {.name = u"OneTimePassword", .form_control_type = "password"},
+              {.role = ElementRole::CURRENT_PASSWORD,
+               .form_control_type = "password"},
+          },
+      .fallback_only = false,
+  }});
+  // Two samples because |CheckTestData| parses the form in two modes: filling
+  // and saving.
+  histogram_tester.ExpectUniqueSample(
+      "PasswordManager.ParserDetectedOtpFieldWithRegex", true, 2);
+}
+
 // The parser should avoid identifying NOT_PASSWORD fields as passwords.
 TEST(FormParserTest, NotPasswordField) {
   CheckTestData({

tools/metrics/histograms/metadata/password/histograms.xml

@@ -2186,6 +2186,17 @@ chromium-metrics-reviews@google.com.
   </summary>
 </histogram>
 
+<histogram name="PasswordManager.ParserDetectedOtpFieldWithRegex"
+    enum="Boolean" expires_after="2023-07-01">
+  <owner>kolos@chromium.org</owner>
+  <owner>shaikhitdin@google.com</owner>
+  <summary>
+    Reports whether the form parser has detected an OTP field with regex.
+    Reported any time when the parser processes a form. Used to compare how
+    often the new and old OTP regexes detect any OTP field.
+  </summary>
+</histogram>
+
 <histogram
     name="PasswordManager.PasswordChangeFlowDuration{EntryPoint}{StartEvent}{EndEvent}"
     units="ms" expires_after="2023-05-09">