[Offline Pages] Adds classification of some prerender FinalStatus codes as canceled operations or a…

components/offline_pages/background/offliner.h

Index: components/offline_pages/background/offliner.h
diff --git a/components/offline_pages/background/offliner.h b/components/offline_pages/background/offliner.h
index 234b84b586987b12febdaf2e58b6bdb3a702e7c7..cafd068634dde132543e8b599ecf2bd15dd56b02 100644
--- a/components/offline_pages/background/offliner.h
+++ b/components/offline_pages/background/offliner.h
@@ -42,6 +42,8 @@ class Offliner {
     REQUEST_COORDINATOR_TIMED_OUT = 8,
     // The loader did not accept/start the request.
     PRERENDERING_NOT_STARTED = 9,
+    // Prerendering failed with hard error so should not retry the request.
+    PRERENDERING_FAILED_NO_RETRY = 10,
     // NOTE: insert new values above this line and update histogram enum too.
     STATUS_COUNT
   };