[OfflinePages] Improve visiblity/handling of "Loading not started" case

chrome/browser/android/offline_pages/prerendering_offliner.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/android/offline_pages/prerendering_offliner.h"
 
 #include "base/bind.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/sys_info.h"
 #include "chrome/browser/android/offline_pages/offline_page_mhtml_archiver.h"
@@ skipping 130 matching lines @@
 
 bool PrerenderingOffliner::LoadAndSave(const SavePageRequest& request,
                                        const CompletionCallback& callback) {
   DCHECK(!pending_request_.get());
 
   if (pending_request_) {
     DVLOG(1) << "Already have pending request";
     return false;
   }
 
-  if (!GetOrCreateLoader()->CanPrerender()) {
-    DVLOG(1) << "Prerendering not allowed/configured";
-    return false;
-  }
-
   // Do not allow loading for custom tabs clients if 3rd party cookies blocked.
   // TODO(dewittj): Revise api to specify policy rather than hard code to
   // name_space.
   if (request.client_id().name_space == kCCTNamespace &&
       (AreThirdPartyCookiesBlocked(browser_context_) ||
        IsNetworkPredictionDisabled(browser_context_))) {
     DVLOG(1) << "WARNING: Unable to load when 3rd party cookies blocked or "
              << "prediction disabled";
     // Record user metrics for third party cookies being disabled or network
     // prediction being disabled.
@@ skipping 102 matching lines @@
           base::android::APPLICATION_STATE_HAS_RUNNING_ACTIVITIES) {
     DVLOG(1) << "App became active, canceling current offlining request";
     SavePageRequest* request = pending_request_.get();
     Cancel();
     completion_callback_.Run(*request,
                              Offliner::RequestStatus::FOREGROUND_CANCELED);
   }
 }
 
 }  // namespace offline_pages