Implement deletion of storage per site.

chrome/browser/ui/webui/settings/site_settings_handler.cc

 // Copyright 2016 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 "chrome/browser/ui/webui/settings/site_settings_handler.h"
 
 #include "base/bind.h"
 #include "base/values.h"
+#include "chrome/browser/browsing_data/browsing_data_local_storage_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/content_settings/core/common/content_settings_types.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/storage_partition.h"
 #include "content/public/browser/web_ui.h"
 #include "ui/base/text/bytes_formatting.h"
 
 namespace settings {
 
 SiteSettingsHandler::SiteSettingsHandler(Profile* profile)
     : profile_(profile) {
 }
 
 SiteSettingsHandler::~SiteSettingsHandler() {
   if (storage_info_fetcher_.get())
     storage_info_fetcher_->RemoveObserver(this);
 }
 
 void SiteSettingsHandler::RegisterMessages() {
   web_ui()->RegisterMessageCallback(
       "fetchUsageTotal",
       base::Bind(&SiteSettingsHandler::HandleFetchUsageTotal,
                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback(
+      "clearUsage",
+      base::Bind(&SiteSettingsHandler::HandleClearUsage,
+                 base::Unretained(this)));
 }
 
 void SiteSettingsHandler::OnGetUsageInfo(
     const storage::UsageInfoEntries& entries) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
   for (const auto& entry : entries) {
     if (entry.usage <= 0) continue;
     if (entry.host == usage_host_) {
       web_ui()->CallJavascriptFunction(
          "settings.WebsiteUsagePrivateApi.returnUsageTotal",
          base::StringValue(entry.host),
-         base::StringValue(ui::FormatBytes(entry.usage)));
-      return;
+         base::StringValue(ui::FormatBytes(entry.usage)),
+         base::FundamentalValue(entry.type));
     }
   }
 }
 
+void SiteSettingsHandler::OnUsageInfoCleared() {
+}
+
 void SiteSettingsHandler::HandleFetchUsageTotal(
     const base::ListValue* args) {
   CHECK_EQ(1U, args->GetSize());
   std::string host;
   CHECK(args->GetString(0, &host));
   usage_host_ = host;
-  storage_info_fetcher_ = new StorageInfoFetcher(
+  storage::QuotaManager* quota_manager =
       content::BrowserContext::GetDefaultStoragePartition(
-          profile_)->GetQuotaManager());
+          profile_)->GetQuotaManager();
+  storage_info_fetcher_ = new StorageInfoFetcher(quota_manager);
   storage_info_fetcher_->AddObserver(this);
-  storage_info_fetcher_->Run();
+  storage_info_fetcher_->FetchStorageInfo();
+}
+
+void SiteSettingsHandler::HandleClearUsage(
+    const base::ListValue* args) {
+  CHECK_EQ(2U, args->GetSize());
+  std::string origin;
+  CHECK(args->GetString(0, &origin));
+  int type;
+  CHECK(args->GetInteger(1, &type));
+
+  GURL url(origin);
+  if (url.is_valid()) {
+    // Start by clearing the storage data asynchronously.
+    storage::QuotaManager* quota_manager =
+        content::BrowserContext::GetDefaultStoragePartition(
+            profile_)->GetQuotaManager();
+    storage_info_fetcher_ = new StorageInfoFetcher(quota_manager);

[michaelpg, 2016/02/03 18:39:13]

Why is it necessary to re-initialize this if it already exists? I'm wondering if
unsetting the scoped_refptr here or above may cause the observer from a previous
call to these functions to not trigger.

[Finnur, 2016/02/04 14:56:58]

I suppose it isn't necessary. I do have an upcoming CL where I'm aiming to
simplify the usage of the fetcher class somewhat; I think it will improve this a
bit, but I don't think we need to reset the fetcher between requests.

+    storage_info_fetcher_->AddObserver(this);
+    storage_info_fetcher_->ClearStorage(
+        url.host(), static_cast<storage::StorageType>(type));
+
+    // Also clear the *local* storage data.
+    scoped_refptr<BrowsingDataLocalStorageHelper> local_storage_helper =
+        new BrowsingDataLocalStorageHelper(profile_);
+    local_storage_helper->DeleteOrigin(url);
+  }
 }
 
 }  // namespace settings