Revert "Speculative revert by sheriff"

content/child/notifications/notification_manager.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/child/notifications/notification_manager.h"
 
+#include <cmath>
+
 #include "base/lazy_instance.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/threading/thread_local.h"
 #include "content/child/notifications/notification_data_conversions.h"
 #include "content/child/notifications/notification_dispatcher.h"
 #include "content/child/service_worker/web_service_worker_registration_impl.h"
 #include "content/child/thread_safe_sender.h"
 #include "content/child/worker_task_runner.h"
 #include "content/public/common/platform_notification_data.h"
@@ skipping 70 matching lines @@
     const blink::WebSerializedOrigin& origin,
     const blink::WebNotificationData& notification_data,
     blink::WebServiceWorkerRegistration* service_worker_registration,
     blink::WebNotificationShowCallbacks* callbacks) {
   DCHECK(service_worker_registration);
   int64 service_worker_registration_id =
       static_cast<WebServiceWorkerRegistrationImpl*>(
           service_worker_registration)->registration_id();
 
   scoped_ptr<blink::WebNotificationShowCallbacks> owned_callbacks(callbacks);
+
+  // Verify that the author-provided payload size does not exceed our limit.
+  // This is an implementation-defined limit to prevent abuse of notification
+  // data as a storage mechanism. A UMA histogram records the requested sizes,
+  // which enables us to track how much data authors are attempting to store.
+  //
+  // If the size exceeds this limit, reject the showNotification() promise. This
+  // is outside of the boundaries set by the specification, but it gives authors
+  // an indication that something has gone wrong.
+  size_t author_data_size = notification_data.data.size();
+  UMA_HISTOGRAM_MEMORY_KB("Notifications.AuthorDataSizeKB",
+                          static_cast<int>(ceil(author_data_size / 1024.0)));
+
+  if (author_data_size > PlatformNotificationData::kMaximumDeveloperDataSize) {
+    owned_callbacks->onError();
+    return;
+  }
+
   if (notification_data.icon.isEmpty()) {
     DisplayPersistentNotification(origin,
                                   notification_data,
                                   service_worker_registration_id,
                                   owned_callbacks.Pass(),
                                   SkBitmap());
     return;
   }
 
   pending_notifications_.FetchPersistentNotificationResources(
@@ skipping 219 matching lines @@
   thread_safe_sender_->Send(
       new PlatformNotificationHostMsg_ShowPersistent(
           request_id,
           service_worker_registration_id,
           GURL(origin.string()),
           icon,
           ToPlatformNotificationData(notification_data)));
 }
 
 }  // namespace content