Add constants for app features

src/plugins/htmlAudioPlayer/plugin.js

@@ -1,3 +1,6 @@
+import { AppFeature } from 'constants/appFeature';
+import { MediaError } from 'types/mediaError';
+
 import browser from '../../scripts/browser';
 import { appHost } from '../../components/apphost';
 import * as htmlMediaHelper from '../../components/htmlMediaHelper';
@@ -5,7 +8,6 @@ import profileBuilder from '../../scripts/browserDeviceProfile';
 import { getIncludeCorsCredentials } from '../../scripts/settings/webSettings';
 import { PluginType } from '../../types/plugin.ts';
 import Events from '../../utils/events.ts';
-import { MediaError } from 'types/mediaError';
 
 function getDefaultProfile() {
     return profileBuilder({});
@@ -278,7 +280,7 @@ class HtmlAudioPlayer {
             }
 
             // TODO: Move volume control to PlaybackManager. Player should just be a wrapper that translates commands into API calls.
-            if (!appHost.supports('physicalvolumecontrol')) {
+            if (!appHost.supports(AppFeature.PhysicalVolumeControl)) {
                 elem.volume = htmlMediaHelper.getSavedVolume();
             }