Restore logic to unsubscribe from permission changes on frame change.

content/browser/permissions/permission_service_impl.cc

Index: content/browser/permissions/permission_service_impl.cc
diff --git a/content/browser/permissions/permission_service_impl.cc b/content/browser/permissions/permission_service_impl.cc
index 75e8a6cd942f2008e8a579cf8feadd617a5b9d12..90767d0599e39d51a5b9c0c105449e0240f2563a 100644
--- a/content/browser/permissions/permission_service_impl.cc
+++ b/content/browser/permissions/permission_service_impl.cc
@@ -257,11 +257,6 @@ void PermissionServiceImpl::AddPermissionObserver(
     last_known_status = current_status;
   }
 
-  BrowserContext* browser_context = context_->GetBrowserContext();
-  DCHECK(browser_context);
-  if (!browser_context->GetPermissionManager())
-    return;
-
   context_->CreateSubscription(PermissionDescriptorToPermissionType(permission),
                                origin, std::move(observer));
 }