feat(browser-support): Add support for WKWebview based browsers.

modules/UI/videolayout/VideoContainer.js

         // explicitly disabled.
         if (interfaceConfig.DISABLE_VIDEO_BACKGROUND
                 || browser.isFirefox()
-                || browser.isSafari()) {
+                || browser.isWebKitBased()) {
             return;
         }
 

react/features/base/environment/environment.js

 export function isSupportedMobileBrowser() {
     return (Platform.OS === 'android' && browser.isChromiumBased())
         || (Platform.OS === 'android' && browser.isFirefox())
-        || (Platform.OS === 'ios' && browser.isSafari());
+        || (Platform.OS === 'ios' && browser.isWebKitBased());
 }
 
 /**

react/features/base/jitsi-local-storage/setup.web.js

  * @returns {void}
  */
 function setupJitsiLocalStorage() {
-    if (jitsiLocalStorage.isLocalStorageDisabled() || browser.isSafari()) {
+    if (jitsiLocalStorage.isLocalStorageDisabled() || browser.isWebKitBased()) {
         const urlParams = parseURLParams(window.location);
 
         try {

react/features/settings/components/web/audio/AudioSettingsContent.js

      * @returns {void}
      */
     async _setTracks() {
-        if (browser.isSafari()) {
+        if (browser.isWebKitBased()) {
 
             // It appears that at the time of this writing, creating audio tracks blocks the browser's main thread for
             // long time on safari. Wasn't able to confirm which part of track creation does the blocking exactly, but