Add ScopedObjCClassSwizzler in base/mac, absorbs objc_method_swizzle and ScopedClassSwizzler

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.
 
 import("//build/config/ui.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
 
@@ skipping 282 matching lines @@
     "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_nsexception_enabler.h",
     "mac/scoped_nsexception_enabler.mm",
     "mac/scoped_nsobject.h",
+    "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",
     "macros.h",
     "md5.cc",
     "md5.h",
     "memory/aligned_memory.cc",
     "memory/aligned_memory.h",
     "memory/discardable_memory.cc",
     "memory/discardable_memory.h",
@@ skipping 801 matching lines @@
     "json/json_writer_unittest.cc",
     "json/string_escape_unittest.cc",
     "lazy_instance_unittest.cc",
     "logging_unittest.cc",
     "mac/bind_objc_block_unittest.mm",
     "mac/foundation_util_unittest.mm",
     "mac/libdispatch_task_runner_unittest.cc",
     "mac/mac_util_unittest.mm",
     "mac/objc_property_releaser_unittest.mm",
     "mac/scoped_nsobject_unittest.mm",
+    "mac/scoped_objc_class_swizzler_unittest.mm",
     "mac/scoped_sending_event_unittest.mm",
     "md5_unittest.cc",
     "memory/aligned_memory_unittest.cc",
     "memory/discardable_memory_manager_unittest.cc",
     "memory/discardable_memory_unittest.cc",
     "memory/linked_ptr_unittest.cc",
     "memory/ref_counted_memory_unittest.cc",
     "memory/ref_counted_unittest.cc",
     "memory/scoped_ptr_unittest.cc",
     "memory/scoped_ptr_unittest.nc",
@@ skipping 315 matching lines @@
 
   unittest_apk("base_unittests_apk") {
     deps = [
       ":base_java",
       ":base_java_unittest_support",
       ":base_unittests",
     ]
     unittests_dep = ":base_unittests"
   }
 }