arc: Enable ARC settings for disable-arc-opt-in-verification

This adds possibility to enable/disable ARC and to view ARC storage
usage in case disable-arc-opt-in-verification. This was primarily used
in test before and now is used by some ARC devs for feature
prototyping.

TEST=Manually, corresponded sections appear in settings and work as
     expected.
BUG=b:120556416

Change-Id: I959bcabd729b76e6aa446d1fd85fe6c2b5f5660b
Reviewed-on: https://chromium-review.googlesource.com/c/1374433Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#616086}

chrome/browser/ui/webui/settings/chromeos/device_storage_handler.cc

@@ -288,10 +288,8 @@ void StorageHandler::OnGetBrowsingDataSize(bool is_site_data, int64_t size) {
 }
 
 void StorageHandler::UpdateAndroidSize() {
-  if (!arc::IsArcPlayStoreEnabledForProfile(profile_) ||
-      arc::IsArcOptInVerificationDisabled()) {
+  if (!arc::IsArcPlayStoreEnabledForProfile(profile_))
     return;
-  }
 
   if (updating_android_size_)
     return;

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

@@ -340,9 +340,8 @@ MdSettingsUI::MdSettingsUI(content::WebUI* web_ui)
   // For AOSP images we don't have the Play Store app. In last case we Android
   // apps settings consists only from root link to Android settings and only
   // visible once settings app is registered.
-  const bool androidAppsVisible = arc::IsArcAllowedForProfile(profile) &&
-                                  !arc::IsArcOptInVerificationDisabled();
-  html_source->AddBoolean("androidAppsVisible", androidAppsVisible);
+  html_source->AddBoolean("androidAppsVisible",
+                          arc::IsArcAllowedForProfile(profile));
   html_source->AddBoolean("havePlayStoreApp", arc::IsPlayStoreAvailable());
 
   // TODO(mash): Support Chrome power settings in Mash. https://crbug.com/644348