Add the Mojo implementation of authenticator.mojom's MakeCredential.

content/browser/BUILD.gn

 # Copyright 2014 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/features.gni")
 import("//build/config/ui.gni")
 import("//gpu/vulkan/features.gni")
 import("//media/media_options.gni")
 import("//ppapi/features/features.gni")
 import("//printing/features/features.gni")
@@ skipping 1508 matching lines @@
     "web_contents/web_contents_view_guest.cc",
     "web_contents/web_contents_view_guest.h",
     "web_contents/web_contents_view_mac.h",
     "web_contents/web_contents_view_mac.mm",
     "web_contents/web_drag_dest_mac.h",
     "web_contents/web_drag_dest_mac.mm",
     "web_contents/web_drag_source_mac.h",
     "web_contents/web_drag_source_mac.mm",
     "web_contents/web_drag_utils_win.cc",
     "web_contents/web_drag_utils_win.h",
+    "webauth/authenticator_impl.cc",
+    "webauth/authenticator_impl.h",
     "websockets/websocket_handshake_request_info_impl.cc",
     "websockets/websocket_handshake_request_info_impl.h",
     "websockets/websocket_impl.cc",
     "websockets/websocket_impl.h",
     "websockets/websocket_manager.cc",
     "websockets/websocket_manager.h",
     "webui/content_web_ui_controller_factory.cc",
     "webui/content_web_ui_controller_factory.h",
     "webui/generic_handler.cc",
     "webui/generic_handler.h",
@@ skipping 611 matching lines @@
   if (!is_component_build) {
     public_deps = [
       ":browser",
     ]
   } else {
     public_deps = [
       "//third_party/leveldatabase",
     ]
   }
 }