[PasswordManager] Put clear-text field password generation behind Finch flag

To allow for a partial roll-out and better metrics, the feature to offer password generation for clear-text fields is put behind a Finch flag.

Bug: 1021897
Change-Id: I4e799b4db354d1285063bb25bd0dc902bfe35b70
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1899380
Commit-Queue: Matthias Körber <koerber@google.com>
Reviewed-by: Vadym Doroshenko <dvadym@chromium.org>
Cr-Commit-Position: refs/heads/master@{#713003}

components/password_manager/core/browser/form_parsing/BUILD.gn

@@ -35,6 +35,7 @@ source_set("unit_tests") {
     "//components/autofill/core/browser",
     "//components/autofill/core/browser/proto",
     "//components/autofill/core/common",
+    "//components/password_manager/core/common",
     "//testing/gmock",
     "//testing/gtest",
     "//url",

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

@@ -146,6 +146,13 @@ bool IsNotUsernameField(const ProcessedField& field) {
   return field.server_hints_not_username;
 }
 
+// Checks if the Finch experiment for offering password generation for
+// server-predicted clear-text fields is enabled.
+bool IsPasswordGenerationForClearTextFieldsEnabled() {
+  return base::FeatureList::IsEnabled(
+      password_manager::features::KEnablePasswordGenerationForClearTextFields);
+}
+
 // Returns true iff |field_type| is one of password types.
 bool IsPasswordPrediction(const CredentialFieldType field_type) {
   switch (field_type) {
@@ -343,6 +350,10 @@ void ParseUsingPredictions(std::vector<ProcessedField>* processed_fields,
         if (!result->new_password) {
           processed_field = FindField(processed_fields, prediction);
           if (processed_field) {
+            if (!IsPasswordGenerationForClearTextFieldsEnabled() &&
+                !processed_field->is_password) {
+              continue;
+            }
             result->new_password = processed_field->field;
             processed_field->is_predicted_as_password = true;
           }
@@ -351,6 +362,10 @@ void ParseUsingPredictions(std::vector<ProcessedField>* processed_fields,
       case CredentialFieldType::kConfirmationPassword:
         processed_field = FindField(processed_fields, prediction);
         if (processed_field) {
+          if (!IsPasswordGenerationForClearTextFieldsEnabled() &&
+              !processed_field->is_password) {
+            continue;
+          }
           result->confirmation_password = processed_field->field;
           processed_field->is_predicted_as_password = true;
         }

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

@@ -15,11 +15,13 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/metrics/histogram_tester.h"
+#include "base/test/scoped_feature_list.h"
 #include "build/build_config.h"
 #include "components/autofill/core/browser/field_types.h"
 #include "components/autofill/core/common/form_data.h"
 #include "components/autofill/core/common/form_field_data.h"
 #include "components/autofill/core/common/password_form.h"
+#include "components/password_manager/core/common/password_manager_features.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "url/gurl.h"
@@ -1114,6 +1116,9 @@ TEST(FormParserTest, ReadonlyFields) {
 }
 
 TEST(FormParserTest, ServerPredictionsForClearTextPasswordFields) {
+  base::test::ScopedFeatureList feature_list;
+  feature_list.InitAndEnableFeature(
+      password_manager::features::KEnablePasswordGenerationForClearTextFields);
   CheckTestData({
       {
           .description_for_logging = "Server prediction for account change "

components/password_manager/core/browser/password_manager.cc

@@ -133,8 +133,11 @@ bool HasSingleUsernameVote(const FormStructure& form) {
 
 // Returns true if at least one of the fields in |form| has a prediction to be a
 // new-password related field.
-// corresponds to a field for creating or changing a password.
 bool HasNewPasswordVote(const FormStructure& form) {
+  if (!base::FeatureList::IsEnabled(
+          password_manager::features::
+              KEnablePasswordGenerationForClearTextFields))
+    return false;
   for (const auto& field : form) {
     if (field->server_type() == autofill::ACCOUNT_CREATION_PASSWORD ||
         field->server_type() == autofill::NEW_PASSWORD) {
@@ -195,10 +198,7 @@ void PasswordManager::RegisterLocalPrefs(PrefRegistrySimple* registry) {
 }
 
 PasswordManager::PasswordManager(PasswordManagerClient* client)
-    : client_(client),
-      leak_delegate_(client)
-
-{
+    : client_(client), leak_delegate_(client) {
   DCHECK(client_);
 }
 

components/password_manager/core/browser/password_manager_unittest.cc

@@ -3227,6 +3227,10 @@ TEST_F(PasswordManagerTest, FillSingleUsername) {
 // in marking the password field as eligible for password generation.
 TEST_F(PasswordManagerTest,
        MarkServerPredictedClearTextPasswordFieldEligibleForGeneration) {
+  base::test::ScopedFeatureList feature_list;
+  feature_list.InitAndEnableFeature(
+      password_manager::features::KEnablePasswordGenerationForClearTextFields);
+
   PasswordFormManager::set_wait_for_server_predictions_for_filling(true);
   EXPECT_CALL(client_, IsSavingAndFillingEnabled(_))
       .WillRepeatedly(Return(true));

components/password_manager/core/common/password_manager_features.cc

@@ -25,6 +25,10 @@ const base::Feature kDeleteCorruptedPasswords = {
 const base::Feature kEnablePasswordsAccountStorage = {
     "EnablePasswordsAccountStorage", base::FEATURE_DISABLED_BY_DEFAULT};
 
+const base::Feature KEnablePasswordGenerationForClearTextFields = {
+    "EnablePasswordGenerationForClearTextFields",
+    base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Enables the experiment for the password manager to only fill on account
 // selection, rather than autofilling on page load, with highlighting of fields.
 const base::Feature kFillOnAccountSelect = {"fill-on-account-select",

components/password_manager/core/common/password_manager_features.h

@@ -20,6 +20,7 @@ namespace features {
 extern const base::Feature kEditPasswordsInDesktopSettings;
 extern const base::Feature kDeleteCorruptedPasswords;
 extern const base::Feature kEnablePasswordsAccountStorage;
+extern const base::Feature KEnablePasswordGenerationForClearTextFields;
 extern const base::Feature kFillOnAccountSelect;
 extern const base::Feature kGenerationNoOverwrites;
 extern const base::Feature kGooglePasswordManager;