Hotword API: Disable tests on non-ChromeOS platforms.

chrome/test/BUILD.gn

Index: chrome/test/BUILD.gn
diff --git a/chrome/test/BUILD.gn b/chrome/test/BUILD.gn
index 4ebc88def0d49eb3770a5498d0f0126298419f73..702a2e0dd0f1c552ac5b246a2345e5d2364eaac0 100644
--- a/chrome/test/BUILD.gn
+++ b/chrome/test/BUILD.gn
@@ -1406,7 +1406,6 @@ test("browser_tests") {
       "../browser/extensions/api/font_settings/font_settings_apitest.cc",
       "../browser/extensions/api/gcm/gcm_apitest.cc",
       "../browser/extensions/api/history/history_apitest.cc",
-      "../browser/extensions/api/hotword_private/hotword_private_apitest.cc",
       "../browser/extensions/api/i18n/i18n_apitest.cc",
       "../browser/extensions/api/identity/identity_apitest.cc",
       "../browser/extensions/api/idltest/idltest_apitest.cc",
@@ -2306,6 +2305,7 @@ test("browser_tests") {
         "../browser/download/notification/download_notification_browsertest.cc",
         "../browser/drive/drive_notification_manager_factory_browsertest.cc",
         "../browser/extensions/api/certificate_provider/certificate_provider_apitest.cc",
+        "../browser/extensions/api/hotword_private/hotword_private_apitest.cc",
         "../browser/extensions/api/vpn_provider/vpn_provider_apitest.cc",
         "../browser/ui/ash/launcher/arc_app_launcher_browsertest.cc",
         "../browser/ui/webui/options/chromeos/accounts_options_browsertest.cc",