Show client placeholders for Server LoFi images.

content/child/runtime_features.cc

Index: content/child/runtime_features.cc
diff --git a/content/child/runtime_features.cc b/content/child/runtime_features.cc
index c56132698cf7185ccd58e23d75e028f9dfa814af..c97d6860104bd29042ed5962a17aec34b4c0317a 100644
--- a/content/child/runtime_features.cc
+++ b/content/child/runtime_features.cc
@@ -9,6 +9,7 @@
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/metrics/field_trial.h"
+#include "base/metrics/field_trial_params.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "build/build_config.h"
@@ -386,6 +387,14 @@ void SetRuntimeFeaturesDefaultsAndUpdateFromArgs(
   WebRuntimeFeatures::EnableLocationHardReload(
       base::FeatureList::IsEnabled(features::kLocationHardReload));
 
+  WebRuntimeFeatures::EnableShowClientPlaceholdersForServerLoFi(
+      command_line.HasSwitch(
+          switches::kEnableShowClientPlaceholdersForServerLoFi) ||
+      (!command_line.HasSwitch(
+           switches::kDisableShowClientPlaceholdersForServerLoFi) &&
+       base::GetFieldTrialParamValue("PreviewsClientLoFi",
+                                     "replace_server_placeholders") == "true"));
+
   // Enable explicitly enabled features, and then disable explicitly disabled
   // ones.
   if (command_line.HasSwitch(switches::kEnableBlinkFeatures)) {