Use the /WX flag to have link warnings treated as errors.

media/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/buildflag_header.gni")
 import("//build/config/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/features.gni")
 import("//build/config/linux/pkg_config.gni")
 import("//build/config/ui.gni")
@@ skipping 718 matching lines @@
 
   if (media_use_ffmpeg) {
     # Direct dependency required to inherit config.
     deps += [ "//third_party/ffmpeg" ]
   }
 }
 
 # Contains tests for all targets in the "media" folder.
 # TODO(xhwang): Move mojo/capture/remoting tests here where applicable.
 test("media_unittests") {
+  # crbug.com/676418: Suppress symbol import warnings.
+  if (is_win && is_component_build) {
+    ldflags = [
+      "/ignore:4217",
+      "/ignore:4049",
+    ]
+  }
+
   deps = [
     ":unit_tests",
     "//media/audio:unit_tests",
     "//media/base:unit_tests",
     "//media/mojo:unit_tests",
     "//media/test:pipeline_integration_tests",
     "//media/test:run_all_unittests",
   ]
 
   if (is_android) {
@@ skipping 209 matching lines @@
   fuzzer_test("media_mp4_avcc_parser_fuzzer") {
     sources = [
       "formats/mp4/mp4_avcc_parser_fuzzer.cc",
     ]
     deps = [
       ":media",
       "//base",
     ]
   }
 }