Add a null check for PermissionBubbleManager::FromWebcontents.

chrome/browser/notifications/desktop_notification_service.cc

Index: chrome/browser/notifications/desktop_notification_service.cc
diff --git a/chrome/browser/notifications/desktop_notification_service.cc b/chrome/browser/notifications/desktop_notification_service.cc
index bde800ce9cb16ffbe0f3c6af073e3b280f8a60cf..184d3d0910d27be76aafc68ad9aadff120dbfde9 100644
--- a/chrome/browser/notifications/desktop_notification_service.cc
+++ b/chrome/browser/notifications/desktop_notification_service.cc
@@ -514,12 +514,14 @@ void DesktopNotificationService::RequestPermission(
     if (PermissionBubbleManager::Enabled()) {
       PermissionBubbleManager* bubble_manager =
           PermissionBubbleManager::FromWebContents(web_contents);
-      bubble_manager->AddRequest(new NotificationPermissionRequest(
-          this,
-          origin,
-          DisplayNameForOriginInProcessId(
-              origin, render_frame_host->GetProcess()->GetID()),
-          callback));
+      if (bubble_manager) {
+        bubble_manager->AddRequest(new NotificationPermissionRequest(
+            this,
+            origin,
+            DisplayNameForOriginInProcessId(
+                origin, render_frame_host->GetProcess()->GetID()),
+            callback));
+      }
       return;
     }