Add InfoBar delegate for previews

components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.cc

Index: components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.cc
diff --git a/components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.cc b/components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.cc
index b2c01d196ee498ef9f2881c7bba40ee4ff914982..8bd6b35d6280a94c2724e200f942a6b46ff5cb34 100644
--- a/components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.cc
+++ b/components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.cc
@@ -199,13 +199,15 @@ const char kHttpOriginalContentLength[] = "http_original_content_length";
 const char kLoFiImplicitOptOutEpoch[] =
     "data_reduction_lo_fi.implicit_opt_out_epoch";
 
-// An integer pref that contains the number of times that "Load images" Lo-Fi
-// snackbar has been shown for the current session.
-const char kLoFiSnackbarsShownPerSession[] =
+// An integer pref that contains the number of times that "Load original" Lo-Fi
+// UI has been shown for the current session. Note the naming of the pref is due
+// to the fact that this UI was originally a snackbar, and has since been
+// changed.
+const char kLoFiUIShownPerSession[] =
     "data_reduction_lo_fi.load_images_snackbars_shown_per_session";
 
-// An integer pref that contains the number of times that "Load images" has been
-// requested on the Lo-Fi snackbar for the current session.
+// An integer pref that contains the number of times that loading the images has
+// been requested from the Lo-Fi UI for the current session.
 const char kLoFiLoadImagesPerSession[] =
     "data_reduction_lo_fi.load_images_requests_per_session";