Add histograms for Enhanced Safe Browsing CRX allowlist

Add histograms to count the number enabled and disabled extensions that
are not present in the Enhanced Safe Browsing CRX allowlist per profile.
The metrics are separated for all users versus Enhanced Safe Browsing
users.

Bug: 1153873
Change-Id: I84f167042fe63299b8da0669c9d117bf136090e1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2627827
Commit-Queue: Jeff Cyr <jeffcyr@google.com>
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843932}

chrome/browser/extensions/installed_loader.cc

@@ -29,6 +29,7 @@
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/common/url_constants.h"
+#include "extensions/browser/allowlist_state.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_registry.h"
@@ -370,6 +371,8 @@ void InstalledLoader::RecordExtensionsMetrics() {
   int off_store_item_count = 0;
   int web_request_blocking_count = 0;
   int web_request_count = 0;
+  int enabled_not_allowlisted_count = 0;
+  int disabled_not_allowlisted_count = 0;
 
   const ExtensionSet& extensions = extension_registry_->enabled_extensions();
   for (ExtensionSet::const_iterator iter = extensions.begin();
@@ -600,6 +603,12 @@ void InstalledLoader::RecordExtensionsMetrics() {
             num_granted_hosts);
       }
     }
+
+    if (extension_prefs_->GetExtensionAllowlistState(extension->id()) ==
+        ALLOWLIST_NOT_ALLOWLISTED) {
+      // Record the number of not allowlisted enabled extensions.
+      ++enabled_not_allowlisted_count;
+    }
   }
 
   const ExtensionSet& disabled_extensions =
@@ -624,6 +633,12 @@ void InstalledLoader::RecordExtensionsMetrics() {
                                   EXTERNAL_ITEM_MAX_ITEMS);
       }
     }
+
+    if (extension_prefs_->GetExtensionAllowlistState((*ex)->id()) ==
+        ALLOWLIST_NOT_ALLOWLISTED) {
+      // Record the number of not allowlisted disabled extensions.
+      ++disabled_not_allowlisted_count;
+    }
   }
 
   base::UmaHistogramCounts100("Extensions.LoadApp",
@@ -684,6 +699,16 @@ void InstalledLoader::RecordExtensionsMetrics() {
   base::UmaHistogramCounts100("Extensions.WebRequestBlockingCount",
                               web_request_blocking_count);
   base::UmaHistogramCounts100("Extensions.WebRequestCount", web_request_count);
+  base::UmaHistogramCounts100("Extensions.NotAllowlistedEnabled",
+                              enabled_not_allowlisted_count);
+  base::UmaHistogramCounts100("Extensions.NotAllowlistedDisabled",
+                              disabled_not_allowlisted_count);
+  if (safe_browsing::IsEnhancedProtectionEnabled(*profile->GetPrefs())) {
+    base::UmaHistogramCounts100("Extensions.NotAllowlistedEnabledAndEsbUser",
+                                enabled_not_allowlisted_count);
+    base::UmaHistogramCounts100("Extensions.NotAllowlistedDisabledAndEsbUser",
+                                disabled_not_allowlisted_count);
+  }
 }
 
 int InstalledLoader::GetCreationFlags(const ExtensionInfo* info) {

tools/metrics/histograms/histograms_xml/extensions/histograms.xml

@@ -2776,6 +2776,50 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
+<histogram name="Extensions.NotAllowlistedDisabled" units="extensions"
+    expires_after="2021-06-01">
+  <owner>jeffcyr@google.com</owner>
+  <owner>lucferron@chromium.org</owner>
+  <summary>
+    The total number of disabled extensions that are not present in the Enhanced
+    Safe Browsing CRX allowlist. Recorded for all users on profile
+    initialization.
+  </summary>
+</histogram>
+
+<histogram name="Extensions.NotAllowlistedDisabledAndEsbUser"
+    units="extensions" expires_after="2021-06-01">
+  <owner>jeffcyr@google.com</owner>
+  <owner>lucferron@chromium.org</owner>
+  <summary>
+    The total number of disabled extensions that are not present in the Enhanced
+    Safe Browsing CRX allowlist. Recorded for only for Enhanced Safe Browsing
+    users on profile initialization.
+  </summary>
+</histogram>
+
+<histogram name="Extensions.NotAllowlistedEnabled" units="extensions"
+    expires_after="2021-06-01">
+  <owner>jeffcyr@google.com</owner>
+  <owner>lucferron@chromium.org</owner>
+  <summary>
+    The total number of enabled extensions that are not present in the Enhanced
+    Safe Browsing CRX allowlist. Recorded for all users on profile
+    initialization.
+  </summary>
+</histogram>
+
+<histogram name="Extensions.NotAllowlistedEnabledAndEsbUser" units="extensions"
+    expires_after="2021-06-01">
+  <owner>jeffcyr@google.com</owner>
+  <owner>lucferron@chromium.org</owner>
+  <summary>
+    The total number of enabled extensions that are not present in the Enhanced
+    Safe Browsing CRX allowlist. Recorded for only for Enhanced Safe Browsing
+    users on profile initialization.
+  </summary>
+</histogram>
+
 <histogram name="Extensions.Permissions_AutoDisable3"
     enum="ExtensionPermission3" expires_after="2020-12-01">
   <owner>rdevlin.cronin@chromium.org</owner>