[ObjC ARC] Converts ios/chrome/test/earl_grey:ios_chrome_device_check_egtests to ARC.

ios/chrome/test/earl_grey/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("//ios/chrome/test/earl_grey/chrome_ios_eg_test.gni")
 
 group("all_tests") {
   testonly = true
   deps = [
     ":ios_chrome_device_check_egtests",
@@ skipping 80 matching lines @@
     # Depends on all EarlGrey test suites to create multitasking tests suite.
     ":ios_chrome_integration_egtests_deps_group",
     ":ios_chrome_settings_egtests_deps_group",
     ":ios_chrome_ui_egtests_deps_group",
     ":ios_chrome_web_egtests_deps_group",
   ]
 
   eg_main_application_delegate = "MultitaskingTestApplicationDelegate"
 }
 
 chrome_ios_eg_test("ios_chrome_device_check_egtests") {

[sdefresne, 2017/05/16 08:26:20]

I think a better change would be to allow overriding "configs" for
"chrome_ios_eg_tests" template. You should add the following to
ios/chrome/test/earl_grey/chrome_ios_eg_test.gni, below the definition of
"chrome_ios_eg_test" template:

set_defaults("chrome_ios_eg_test") {
  configs = default_executable_configs
}

That should be enough to allow you to change this file to the following:

chrome_ios_eg_test("ios_chrome_device_check_egtests") {
  configs += [ "//build/config/compiler:enable_arc" ]
  sources = [
    "device_check_egtest.mm",
  ]
  deps = [
    ":test_support",
    "//ios/third_party/earl_grey",
    "//url",
  ]
}

[liaoyuke, 2017/05/16 16:08:31]

Hi Sylvain,

Thank you for the detailed explanation!

I've updated the CL according to your comments, however, it seems that [
"//build/config/compiler:enable_arc" ] still doesn't apply to
"device_check_egtest.mm".

I debugged a little bit, but couldn't understand, do you have any thoughts?

+  deps = [
+    ":device_check_sources",
+  ]
+}
+
+source_set("device_check_sources") {
+  configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
     "device_check_egtest.mm",

[sdefresne, 2017/05/16 08:27:17]

This CL needs to add guards to "device_check_egtest.mm" file to prevent
compiling it without ARC.

[liaoyuke, 2017/05/16 16:08:31]

Done.

   ]
+  testonly = true
   deps = [
     ":test_support",
     "//ios/third_party/earl_grey",
     "//url",
   ]
 }
 
 chrome_ios_eg_test("ios_chrome_flaky_egtests") {
   deps = [
     ":test_support",
@@ skipping 88 matching lines @@
 
 source_set("hooks") {
   testonly = true
   sources = [
     "eg_tests_hook.mm",
   ]
   deps = [
     "//ios/chrome/app:tests_hook",
   ]
 }