[iOS/OS X] Allow base::scoped_nsobject<> to be used when ARC is enabled.

base/BUILD.gn

 # Copyright (c) 2013 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.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 411 matching lines @@
     "mac/mach_port_broker.mm",
     "mac/mach_port_util.cc",
     "mac/mach_port_util.h",
     "mac/objc_property_releaser.h",
     "mac/objc_property_releaser.mm",
     "mac/os_crash_dumps.cc",
     "mac/os_crash_dumps.h",
     "mac/scoped_aedesc.h",
     "mac/scoped_authorizationref.h",
     "mac/scoped_block.h",
+    "mac/scoped_block.mm",
     "mac/scoped_cftyperef.h",
     "mac/scoped_ioobject.h",
     "mac/scoped_ioplugininterface.h",
     "mac/scoped_launch_data.h",
     "mac/scoped_mach_port.cc",
     "mac/scoped_mach_port.h",
     "mac/scoped_mach_vm.cc",
     "mac/scoped_mach_vm.h",
     "mac/scoped_nsautorelease_pool.h",
     "mac/scoped_nsautorelease_pool.mm",
     "mac/scoped_nsobject.h",
+    "mac/scoped_nsobject.mm",
     "mac/scoped_objc_class_swizzler.h",
     "mac/scoped_objc_class_swizzler.mm",
     "mac/scoped_sending_event.h",
     "mac/scoped_sending_event.mm",
     "mac/sdk_forward_declarations.h",
     "mac/sdk_forward_declarations.mm",
     "macros.h",
     "md5.cc",
     "md5.h",
     "memory/aligned_memory.cc",
@@ skipping 932 matching lines @@
       "mac/call_with_eh_frame.cc",
       "mac/call_with_eh_frame.h",
       "mac/foundation_util.h",
       "mac/foundation_util.mm",
       "mac/mac_logging.h",
       "mac/mac_logging.mm",
       "mac/mach_logging.cc",
       "mac/mach_logging.h",
       "mac/objc_property_releaser.h",
       "mac/objc_property_releaser.mm",
+      "mac/scoped_block.h",
+      "mac/scoped_block.mm",
       "mac/scoped_mach_port.cc",
       "mac/scoped_mach_port.h",
       "mac/scoped_mach_vm.cc",
       "mac/scoped_mach_vm.h",
       "mac/scoped_nsautorelease_pool.h",
       "mac/scoped_nsautorelease_pool.mm",
       "mac/scoped_nsobject.h",
+      "mac/scoped_nsobject.mm",
       "mac/scoped_objc_class_swizzler.h",
       "mac/scoped_objc_class_swizzler.mm",
+      "mac/scoped_typeref.h",
       "memory/shared_memory_posix.cc",
       "message_loop/message_pump_mac.h",
       "message_loop/message_pump_mac.mm",
       "process/memory_stubs.cc",
       "strings/sys_string_conversions_mac.mm",
       "threading/platform_thread_mac.mm",
       "time/time_mac.cc",
     ]
 
     set_sources_assignment_filter(sources_assignment_filter)
@@ skipping 229 matching lines @@
   testonly = true
   sources = [
     "test/data",
   ]
   outputs = [
     "{{bundle_resources_dir}}/" +
         "{{source_root_relative_dir}}/{{source_file_part}}",
   ]
 }
 
+if (is_ios || is_mac) {
+  source_set("base_unittests_arc") {
+    testonly = true
+    set_sources_assignment_filter([])
+    sources = [
+      "mac/scoped_nsobject_unittest_arc.mm",
+    ]
+    set_sources_assignment_filter(sources_assignment_filter)
+    configs += [ "//build/config/compiler:enable_arc" ]
+    deps = [
+      ":base",
+      "//testing/gtest",
+    ]
+  }
+}
+
 test("base_unittests") {
   sources = [
     "allocator/tcmalloc_unittest.cc",
     "android/application_status_listener_unittest.cc",
     "android/content_uri_utils_unittest.cc",
     "android/jni_android_unittest.cc",
     "android/jni_array_unittest.cc",
     "android/jni_string_unittest.cc",
     "android/library_loader/library_prefetcher_unittest.cc",
     "android/path_utils_unittest.cc",
@@ skipping 250 matching lines @@
     ":i18n",
     ":message_loop_tests",
     "//base/test:run_all_unittests",
     "//base/test:test_support",
     "//base/third_party/dynamic_annotations",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/icu",
   ]
 
+  if (is_ios || is_mac) {
+    deps += [ ":base_unittests_arc" ]
+  }
+
   public_deps = [
     ":base_unittests_bundle_data",
   ]
 
   # Some unittests depend on the ALLOCATOR_SHIM macro.
   configs += [ "//base/allocator:allocator_shim_define" ]
 
   data = [
     "test/data/",
   ]
@@ skipping 396 matching lines @@
 
   # GYP: //base.gyp:base_java_unittest_support
   android_library("base_java_unittest_support") {
     deps = [
       ":base_java",
     ]
     java_files =
         [ "test/android/java/src/org/chromium/base/ContentUriTestUtils.java" ]
   }
 }