ServiceWorker: Add UMA for storage recovery operation

content/browser/service_worker/service_worker_metrics.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/browser/service_worker/service_worker_metrics.h"
 
 #include "base/metrics/histogram.h"
 #include "base/metrics/user_metrics_action.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/common/content_client.h"
 
 namespace content {
 
 namespace {
 
 void RecordURLMetricOnUI(const GURL& url) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   GetContentClient()->browser()->RecordURLMetric(
       "ServiceWorker.ControlledPageUrl", url);
 }
 
 }  // namespace
 
-// static
 void ServiceWorkerMetrics::CountInitDiskCacheResult(bool result) {
   UMA_HISTOGRAM_BOOLEAN("ServiceWorker.DiskCache.InitResult", result);
 }
 
-// static
 void ServiceWorkerMetrics::CountReadResponseResult(
     ServiceWorkerMetrics::ReadResponseResult result) {
   UMA_HISTOGRAM_ENUMERATION("ServiceWorker.DiskCache.ReadResponseResult",
                             result, NUM_READ_RESPONSE_RESULT_TYPES);
 }
 
-// static
 void ServiceWorkerMetrics::CountWriteResponseResult(
     ServiceWorkerMetrics::WriteResponseResult result) {
   UMA_HISTOGRAM_ENUMERATION("ServiceWorker.DiskCache.WriteResponseResult",
                             result, NUM_WRITE_RESPONSE_RESULT_TYPES);
 }
 
-// static
 void ServiceWorkerMetrics::CountOpenDatabaseResult(
     ServiceWorkerDatabase::Status status) {
   UMA_HISTOGRAM_ENUMERATION("ServiceWorker.Database.OpenResult",
                             status, ServiceWorkerDatabase::STATUS_ERROR_MAX);
 }
 
-// static
 void ServiceWorkerMetrics::CountReadDatabaseResult(
     ServiceWorkerDatabase::Status status) {
   UMA_HISTOGRAM_ENUMERATION("ServiceWorker.Database.ReadResult",
                             status, ServiceWorkerDatabase::STATUS_ERROR_MAX);
 }
 
-// static
 void ServiceWorkerMetrics::CountWriteDatabaseResult(

[Ilya Sherman, 2015/03/25 20:45:08]

Why have you removed the "// static" comments?  They're used pretty consistently
throughout the Chromium codebase.  (Note: I don't feel strongly about this.)

[nhiroki, 2015/03/25 23:08:08]

I think such comments aren't informative in this class because this is designed
to contain only static functions and annotated with
DISALLOW_IMPLICIT_CONSTRUCTORS().

     ServiceWorkerDatabase::Status status) {
   UMA_HISTOGRAM_ENUMERATION("ServiceWorker.Database.WriteResult",
                             status, ServiceWorkerDatabase::STATUS_ERROR_MAX);
 }
 
-// static
+void ServiceWorkerMetrics::RecordDestroyDatabaseResult(
+    ServiceWorkerDatabase::Status status) {
+  UMA_HISTOGRAM_ENUMERATION("ServiceWorker.Database.DestroyDatabase", status,
+                            ServiceWorkerDatabase::STATUS_ERROR_MAX);
+}
+
+void ServiceWorkerMetrics::RecordDeleteAndStartOverResult(
+    DeleteAndStartOverResult result) {
+  UMA_HISTOGRAM_ENUMERATION("ServiceWorker.Storage.DeleteAndStartOverResult",
+                            result, NUM_DELETE_AND_START_OVER_RESULT_TYPES);
+}
+
 void ServiceWorkerMetrics::CountControlledPageLoad(const GURL& url) {
   RecordAction(base::UserMetricsAction("ServiceWorker.ControlledPageLoad"));
   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                           base::Bind(&RecordURLMetricOnUI, url));
 }
 
 }  // namespace content