Content Settings: Add RevocationObserver to measure when permissions are revoked

chrome/browser/permissions/permission_manager.cc

Index: chrome/browser/permissions/permission_manager.cc
diff --git a/chrome/browser/permissions/permission_manager.cc b/chrome/browser/permissions/permission_manager.cc
index c1a719a45241bd34562014df15d8fad512357426..440f18d175a372a03676ecef8fca2a18819120c5 100644
--- a/chrome/browser/permissions/permission_manager.cc
+++ b/chrome/browser/permissions/permission_manager.cc
@@ -12,6 +12,8 @@
 #include "chrome/browser/permissions/permission_context.h"
 #include "chrome/browser/permissions/permission_context_base.h"
 #include "chrome/browser/permissions/permission_request_id.h"
+#include "chrome/browser/permissions/permission_uma_util.h"
+#include "chrome/browser/permissions/permission_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/tab_contents/tab_util.h"
 #include "components/content_settings/core/browser/host_content_settings_map.h"
@@ -198,12 +200,11 @@ struct PermissionManager::Subscription {
 PermissionManager::PermissionManager(Profile* profile)
     : profile_(profile),
       weak_ptr_factory_(this) {
+  HostContentSettingsMapFactory::GetForProfile(profile_)->AddObserver(this);
 }
 
 PermissionManager::~PermissionManager() {
-  if (!subscriptions_.IsEmpty())
-    HostContentSettingsMapFactory::GetForProfile(profile_)
-        ->RemoveObserver(this);
+  HostContentSettingsMapFactory::GetForProfile(profile_)->RemoveObserver(this);
 }
 
 int PermissionManager::RequestPermission(
@@ -351,8 +352,6 @@ int PermissionManager::SubscribePermissionStatusChange(
     const GURL& requesting_origin,
     const GURL& embedding_origin,
     const base::Callback<void(PermissionStatus)>& callback) {
-  if (subscriptions_.IsEmpty())
-    HostContentSettingsMapFactory::GetForProfile(profile_)->AddObserver(this);
 
   Subscription* subscription = new Subscription();
   subscription->permission = permission;
@@ -375,10 +374,6 @@ int PermissionManager::SubscribePermissionStatusChange(
 void PermissionManager::UnsubscribePermissionStatusChange(int subscription_id) {
   // Whether |subscription_id| is known will be checked by the Remove() call.
   subscriptions_.Remove(subscription_id);
-
-  if (subscriptions_.IsEmpty())
-    HostContentSettingsMapFactory::GetForProfile(profile_)
-        ->RemoveObserver(this);
 }
 
 bool PermissionManager::IsPermissionBubbleManagerMissing(
@@ -429,3 +424,13 @@ void PermissionManager::OnContentSettingChanged(
   for (const auto& callback : callbacks)
     callback.Run();
 }
+
+void PermissionManager::OnContentSettingRevoked(
+    const GURL& primary_url,
+    const GURL& secondary_url,
+    ContentSettingsType content_type,
+    std::string resource_identifier) {
+  PermissionType permission_type;
+  if (PermissionUtil::GetPermissionType(content_type, &permission_type))
+    PermissionUmaUtil::PermissionRevoked(permission_type, primary_url);
+}