Enable SiteEngagementEvictionPolicy behind --enable-site-eviction-policy flag.

chrome/browser/chrome_content_browser_client.cc

 // Copyright (c) 2012 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/chrome_content_browser_client.h"
 
 #include <map>
 #include <set>
 #include <utility>
 #include <vector>
@@ skipping 21 matching lines @@
 #include "chrome/browser/character_encoding.h"
 #include "chrome/browser/chrome_content_browser_client_parts.h"
 #include "chrome/browser/chrome_net_benchmarking_message_filter.h"
 #include "chrome/browser/chrome_quota_permission_context.h"
 #include "chrome/browser/content_settings/cookie_settings_factory.h"
 #include "chrome/browser/content_settings/host_content_settings_map_factory.h"
 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
 #include "chrome/browser/defaults.h"
 #include "chrome/browser/devtools/chrome_devtools_manager_delegate.h"
 #include "chrome/browser/download/download_prefs.h"
+#include "chrome/browser/engagement/site_engagement_eviction_policy.h"
 #include "chrome/browser/font_family_cache.h"
 #include "chrome/browser/geolocation/chrome_access_token_store.h"
 #include "chrome/browser/media/media_capture_devices_dispatcher.h"
 #include "chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.h"
 #include "chrome/browser/nacl_host/nacl_browser_delegate_impl.h"
 #include "chrome/browser/net/chrome_net_log.h"
 #include "chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_settings.h"
 #include "chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_settings_factory.h"
 #include "chrome/browser/notifications/platform_notification_service_impl.h"
 #include "chrome/browser/platform_util.h"
@@ skipping 83 matching lines @@
 #include "device/devices_app/public/cpp/constants.h"
 #include "device/devices_app/public/cpp/devices_app_factory.h"
 #include "gin/v8_initializer.h"
 #include "mojo/application/public/cpp/application_delegate.h"
 #include "net/base/mime_util.h"
 #include "net/cookies/canonical_cookie.h"
 #include "net/cookies/cookie_options.h"
 #include "net/ssl/ssl_cert_request_info.h"
 #include "ppapi/host/ppapi_host.h"
 #include "storage/browser/fileapi/external_mount_points.h"
+#include "storage/browser/quota/quota_manager.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/resources/grit/ui_resources.h"
 
 #if defined(OS_WIN)
 #include "base/win/windows_version.h"
 #include "chrome/browser/chrome_browser_main_win.h"
 #include "sandbox/win/src/sandbox_policy.h"
 #elif defined(OS_MACOSX)
 #include "chrome/browser/chrome_browser_main_mac.h"
@@ skipping 1721 matching lines @@
 #endif
 
   return NULL;
 }
 
 QuotaPermissionContext*
 ChromeContentBrowserClient::CreateQuotaPermissionContext() {
   return new ChromeQuotaPermissionContext();
 }
 
+void ChromeContentBrowserClient::AddQuotaEvictionPolicies(

[raymes, 2015/09/24 01:55:30]

I guess the alternate API would look like:
GetTemporaryStorageEvictionPolicy(context, quota_manager) 

This seems a bit clearer to me but I guess this partly related back to the
question of whether we ever expected there to be eviction policies for other
types.

If we did this, we could even return the LRU policy here when the site
engagement service is disabled and get rid of the map in QuotaManager (i.e.
always require the policy to be specified, no default policy). WDYT?

[calamity, 2015/10/26 03:01:57]

Done.

+    content::BrowserContext* context, storage::QuotaManager* quota_manager) {
+  if (SiteEngagementEvictionPolicy::IsEnabled()) {
+    quota_manager->SetQuotaEvictionPolicy(
+        storage::kStorageTypeTemporary,
+        make_scoped_ptr(
+            new SiteEngagementEvictionPolicy(storage::kStorageTypeTemporary,
+                                             quota_manager, context)));
+  }
+}
+
 void ChromeContentBrowserClient::AllowCertificateError(
     int render_process_id,
     int render_frame_id,
     int cert_error,
     const net::SSLInfo& ssl_info,
     const GURL& request_url,
     ResourceType resource_type,
     bool overridable,
     bool strict_enforcement,
     bool expired_previous_decision,
@@ skipping 773 matching lines @@
   if (channel <= kMaxDisableEncryptionChannel) {
     static const char* const kWebRtcDevSwitchNames[] = {
       switches::kDisableWebRtcEncryption,
     };
     to_command_line->CopySwitchesFrom(from_command_line,
                                       kWebRtcDevSwitchNames,
                                       arraysize(kWebRtcDevSwitchNames));
   }
 }
 #endif  // defined(ENABLE_WEBRTC)