Sync: Tiny cleanup in ServerConnectionManager

This removes one entry of the ServerConnectionCode enum which is unused,
and removes an obsolete TODO.

Bug: none
Change-Id: I19a6653d30fc8f6c2bfd7d7d45c6a7a57f6f0473
Reviewed-on: https://chromium-review.googlesource.com/c/1290951Reviewed-by: vitaliii <vitaliii@chromium.org>
Commit-Queue: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601118}

components/sync/engine_impl/net/server_connection_manager.cc

@@ -48,7 +48,6 @@ const char* HttpResponse::GetServerConnectionCodeString(
     ENUM_CASE(SYNC_SERVER_ERROR);
     ENUM_CASE(SYNC_AUTH_ERROR);
     ENUM_CASE(SERVER_CONNECTION_OK);
-    ENUM_CASE(RETRY);
   }
   NOTREACHED();
   return "";

components/sync/engine_impl/net/server_connection_manager.h

@@ -43,26 +43,15 @@ struct HttpResponse {
     IO_ERROR,
 
     // SYNC_SERVER_ERROR is returned when the HTTP status code indicates that
-    // a non-auth error has occured.
+    // a non-auth error has occurred.
     SYNC_SERVER_ERROR,
 
     // SYNC_AUTH_ERROR is returned when the HTTP status code indicates that an
-    // auth error has occured (i.e. a 401 or sync-specific AUTH_INVALID
-    // response)
-    // TODO(tim): Caring about AUTH_INVALID is a layering violation. But
-    // this app-specific logic is being added as a stable branch hotfix so
-    // minimal changes prevail for the moment.  Fix this! Bug 35060.
+    // auth error has occurred (i.e. a 401).
     SYNC_AUTH_ERROR,
 
     // SERVER_CONNECTION_OK is returned when request was handled correctly.
     SERVER_CONNECTION_OK,
-
-    // RETRY is returned when a Commit request fails with a RETRY response from
-    // the server.
-    //
-    // TODO(idana): the server no longer returns RETRY so we should remove this
-    // value.
-    RETRY,
   };
 
   // The HTTP Status code.

components/sync/engine_impl/syncer_proto_util.cc

@@ -93,8 +93,6 @@ SyncerError ServerConnectionErrorAsSyncerError(
       return SYNC_SERVER_ERROR;
     case HttpResponse::SYNC_AUTH_ERROR:
       return SYNC_AUTH_ERROR;
-    case HttpResponse::RETRY:
-      return SERVER_RETURN_TRANSIENT_ERROR;
     case HttpResponse::SERVER_CONNECTION_OK:
     case HttpResponse::NONE:
     default: