Change Lo-Fi bool to bitmask to support multiple Previews types

content/public/browser/resource_dispatcher_host_delegate.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 "content/public/browser/resource_dispatcher_host_delegate.h"
 
 #include "content/public/browser/navigation_data.h"
 #include "content/public/browser/resource_request_info.h"
 #include "content/public/browser/stream_info.h"
 #include "net/ssl/client_cert_store.h"
@@ skipping 69 matching lines @@
 }
 
 void ResourceDispatcherHostDelegate::RequestComplete(
     net::URLRequest* url_request,
     int net_error) {}
 
 // Deprecated.
 void ResourceDispatcherHostDelegate::RequestComplete(
     net::URLRequest* url_request) {}
 
-bool ResourceDispatcherHostDelegate::ShouldEnableLoFiMode(
+PreviewsState ResourceDispatcherHostDelegate::GetPreviewsState(
     const net::URLRequest& url_request,
     content::ResourceContext* resource_context) {
-  return false;
+  return PREVIEWS_UNSPECIFIED;
 }
 
 NavigationData* ResourceDispatcherHostDelegate::GetNavigationData(
     net::URLRequest* request) const {
   return nullptr;
 }
 
 std::unique_ptr<net::ClientCertStore>
 ResourceDispatcherHostDelegate::CreateClientCertStore(
     ResourceContext* resource_context) {
   return std::unique_ptr<net::ClientCertStore>();
 }
 
 void ResourceDispatcherHostDelegate::OnAbortedFrameLoad(
     const GURL& url,
     base::TimeDelta request_loading_time) {
 }
 
 ResourceDispatcherHostDelegate::~ResourceDispatcherHostDelegate() {
 }
 
 }  // namespace content