ServiceWorker: Add UMA for storage recovery operation

content/browser/service_worker/service_worker_storage.cc

 // Copyright 2013 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/browser/service_worker/service_worker_storage.h"
 
 #include "base/bind_helpers.h"
 #include "base/files/file_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/sequenced_task_runner.h"
@@ skipping 1738 matching lines @@
 }
 
 void ServiceWorkerStorage::DidDeleteDatabase(
     const StatusCallback& callback,
     ServiceWorkerDatabase::Status status) {
   DCHECK_EQ(DISABLED, state_);
   if (status != ServiceWorkerDatabase::STATUS_OK) {
     // Give up the corruption recovery until the browser restarts.
     LOG(ERROR) << "Failed to delete the database: "
                << ServiceWorkerDatabase::StatusToString(status);
+    ServiceWorkerMetrics::RecordDeleteAndStartOverResult(
+        ServiceWorkerMetrics::DELETE_DATABASE_ERROR);
     callback.Run(DatabaseStatusToStatusCode(status));
     return;
   }
   DVLOG(1) << "Deleted ServiceWorkerDatabase successfully.";
 
   // Delete the disk cache on the cache thread.
   // TODO(nhiroki): What if there is a bunch of files in the cache directory?
   // Deleting the directory could take a long time and restart could be delayed.
   // We should probably rename the directory and delete it later.
   PostTaskAndReplyWithResult(
       database_task_manager_->GetTaskRunner(),
       FROM_HERE,
       base::Bind(&base::DeleteFile, GetDiskCachePath(), true),
       base::Bind(&ServiceWorkerStorage::DidDeleteDiskCache,
                  weak_factory_.GetWeakPtr(),
                  callback));
 }
 
 void ServiceWorkerStorage::DidDeleteDiskCache(
     const StatusCallback& callback, bool result) {
   DCHECK_EQ(DISABLED, state_);
   if (!result) {
     // Give up the corruption recovery until the browser restarts.
     LOG(ERROR) << "Failed to delete the diskcache.";
+    ServiceWorkerMetrics::RecordDeleteAndStartOverResult(
+        ServiceWorkerMetrics::DELETE_DISK_CACHE_ERROR);
     callback.Run(SERVICE_WORKER_ERROR_FAILED);
     return;
   }
   DVLOG(1) << "Deleted ServiceWorkerDiskCache successfully.";
+  ServiceWorkerMetrics::RecordDeleteAndStartOverResult(
+      ServiceWorkerMetrics::DELETE_OK);
   callback.Run(SERVICE_WORKER_OK);
 }
 
 }  // namespace content