[WIP] off-main-thread loading

chrome/browser/flag_descriptions.cc

Index: chrome/browser/flag_descriptions.cc
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index c50dc27298c96c8d8066bcc206322cbc0ae9503f..5db49ec38f8d8ffab0813ae79c4526f1e92b63c0 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -99,6 +99,13 @@ const char kSpeculativePrefetchDescription[] =
     R"*("Learning" means that only the database construction is enabled, )*"
     R"*("Prefetching" that learning and prefetching are enabled.)*";
 
+const char kOffMainThreadFetchName[] =
+    "Experimental resource fetch optimizations for workers";
+
+const char kOffMainThreadFetchDescription[] =
+    "If enabled, the resource fetch in worker threads will not be blocked by "
+    "the busy main thread.";
+
 //  Force Tablet Mode
 
 const char kForceTabletModeName[] = "Force Tablet Mode";