Enable RL by default

components/reading_list/core/BUILD.gn

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/buildflag_header.gni")
+import("//components/reading_list/core/reading_list.gni")
+
+buildflag_header("enable_flags") {
+  header = "reading_list_enable_flags.h"
+  header_dir = "components/reading_list/core"
+  enabled = is_ios && enable_reading_list

[sdefresne, 2016/12/09 15:10:59]

nit: please name this "_enabled" (variable starting with an underscore are
private, thus it won't be passed to the template and won't break if the template
ever add a parameter named "enabled").

[Olivier, 2016/12/09 15:27:38]

Done.

+  flags = [ "ENABLE_READING_LIST=$enabled" ]
+}
+
 source_set("core") {
   sources = [
     "reading_list_switches.cc",
     "reading_list_switches.h",
   ]
   deps = [
+    ":enable_flags",
     "//base",
   ]
 }