Use the Previews Black List for server previews

chrome/browser/loader/chrome_resource_dispatcher_host_delegate.cc

Index: chrome/browser/loader/chrome_resource_dispatcher_host_delegate.cc
diff --git a/chrome/browser/loader/chrome_resource_dispatcher_host_delegate.cc b/chrome/browser/loader/chrome_resource_dispatcher_host_delegate.cc
index 0a2881c3935ddbf8f5c5a81cb02c0d8df8bbb334..102e08b53b71c4374cfe2ac779b568e51ab38e18 100644
--- a/chrome/browser/loader/chrome_resource_dispatcher_host_delegate.cc
+++ b/chrome/browser/loader/chrome_resource_dispatcher_host_delegate.cc
@@ -892,12 +892,14 @@ content::PreviewsState ChromeResourceDispatcherHostDelegate::GetPreviewsState(
   content::PreviewsState previews_state = content::PREVIEWS_UNSPECIFIED;
 
   if (data_reduction_proxy_io_data) {
-    if (data_reduction_proxy_io_data->ShouldEnableLoFi(url_request))
+    previews::PreviewsIOData* previews_io_data = io_data->previews_io_data();

[megjablon, 2017/05/10 19:11:23]

Should there be a null check here? Can we move this line above and do: 

if (data_reduction_proxy_io_data && previews_io_data)

and remove the previews_io_data check in the if statement on 907.

[RyanSturm, 2017/05/10 19:57:02]

Done.

+    if (data_reduction_proxy_io_data->ShouldEnableLoFi(url_request,
+                                                       previews_io_data))
       previews_state |= content::SERVER_LOFI_ON;
-    if (data_reduction_proxy_io_data->ShouldEnableLitePages(url_request))
+    if (data_reduction_proxy_io_data->ShouldEnableLitePages(url_request,
+                                                            previews_io_data))
       previews_state |= content::SERVER_LITE_PAGE_ON;
 
-    previews::PreviewsIOData* previews_io_data = io_data->previews_io_data();
     // Check that data saver is enabled, the user isn't opted out of LoFi for
     // the session, and the user is eligible for previews.
     if (data_reduction_proxy_io_data->IsEnabled() &&