pciguard: Add metric for data access protection toggle

Tracks an boolean histogram of whenever the user toggles the
"Data Access Protection" toggle in ChromeOS Settings Privacy page.

(cherry picked from commit 30812b0)

Bug: 1184050
Test: local
Change-Id: I66de1aae26ca8d086192cce2a71e63a0ace00b81
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2733744
Commit-Queue: Jimmy Gong <jimmyxgong@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Regan Hsu <hsuregan@chromium.org>
Reviewed-by: Weilun Shi <sweilun@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#860022}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2743639
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/branch-heads/4430@{#263}
Cr-Branched-From: e5ce7dc-refs/heads/master@{#857950}

chrome/browser/resources/settings/chromeos/pref_to_setting_metric_converter.js

@@ -38,6 +38,14 @@
           value: {intValue: /** @type {number} */ (prefValue)}
         };
 
+      // os_privacy_page/os_privacy_page.js
+      case 'cros.device.peripheral_data_access_enabled':
+        return {
+          setting:
+              chromeos.settings.mojom.Setting.kPeripheralDataAccessProtection,
+          value: {boolValue: /** @type {boolean} */ (prefValue)}
+        };
+
       // pref to setting metric not implemented.
       default:
         return null;

chrome/browser/ui/webui/settings/chromeos/privacy_section.cc

@@ -6,6 +6,7 @@
 
 #include "ash/constants/ash_features.h"
 #include "base/feature_list.h"
+#include "base/metrics/histogram_functions.h"
 #include "base/no_destructor.h"
 #include "build/branding_buildflags.h"
 #include "chrome/browser/ash/login/quick_unlock/quick_unlock_utils.h"
@@ -276,8 +277,15 @@ std::string PrivacySection::GetSectionPath() const {
 
 bool PrivacySection::LogMetric(mojom::Setting setting,
                                base::Value& value) const {
-  // Unimplemented.
-  return false;
+  switch (setting) {
+    case mojom::Setting::kPeripheralDataAccessProtection:
+      base::UmaHistogramBoolean(
+          "ChromeOS.Settings.Privacy.PeripheralDataAccessProtection",
+          value.GetBool());
+      return true;
+    default:
+      return false;
+  }
 }
 
 void PrivacySection::RegisterHierarchy(HierarchyGenerator* generator) const {

tools/metrics/histograms/histograms_xml/chromeos/histograms.xml

@@ -1066,6 +1066,17 @@ incoming reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
+<histogram name="ChromeOS.Settings.Privacy.PeripheralDataAccessProtection"
+    enum="BooleanEnabled" expires_after="2021-11-30">
+  <owner>jimmyxgong@chromium.org</owner>
+  <owner>cros-peripherals@google.com</owner>
+  <summary>
+    Records when the users clicks on the Peripheral Data Access toggle. A true
+    value refers to the user enables peripheral data access protection (toggle
+    is turned on).
+  </summary>
+</histogram>
+
 <histogram name="ChromeOS.Settings.SearchLatency" units="ms"
     expires_after="2021-10-01">
   <owner>khorimoto@chromium.org</owner>