feat(UnsupportedMobileBrowser): do not include protocol in the intent

Do not include the protocol part in the intent URL.

react/features/base/util/uri.js

 /**
  * The {@link RegExp} pattern of the protocol of a URI.
  *
- * @private
+ * FIXME: The URL class exposed by JavaScript will not include the colon in
+ * the protocol field. Also in other places (at the time of this writing:
+ * the UnsupportedMobileBrowser.js) the APP_LINK_SCHEME does not include
+ * the double dots, so things are inconsistent.
+ *
  * @type {string}
  */
-const _URI_PROTOCOL_PATTERN = '([a-z][a-z0-9\\.\\+-]*:)';
+export const URI_PROTOCOL_PATTERN = '([a-z][a-z0-9\\.\\+-]*:)';
 
 /**
  * Fixes the hier-part of a specific URI (string) so that the URI is well-known.
     // hipchat.com
     let regex
         = new RegExp(
-            `^${_URI_PROTOCOL_PATTERN}//hipchat\\.com/video/call/`,
+            `^${URI_PROTOCOL_PATTERN}//hipchat\\.com/video/call/`,
             'gi');
     let match: Array<string> | null = regex.exec(uri);
 
         // enso.me
         regex
             = new RegExp(
-                `^${_URI_PROTOCOL_PATTERN}//enso\\.me/(?:call|meeting)/`,
+                `^${URI_PROTOCOL_PATTERN}//enso\\.me/(?:call|meeting)/`,
                 'gi');
         match = regex.exec(uri);
     }
  * @returns {string}
  */
 function _fixURIStringScheme(uri: string) {
-    const regex = new RegExp(`^${_URI_PROTOCOL_PATTERN}+`, 'gi');
+    const regex = new RegExp(`^${URI_PROTOCOL_PATTERN}+`, 'gi');
     const match: Array<string> | null = regex.exec(uri);
 
     if (match) {
     str = str.replace(/\s/g, '');
 
     // protocol
-    regex = new RegExp(`^${_URI_PROTOCOL_PATTERN}`, 'gi');
+    regex = new RegExp(`^${URI_PROTOCOL_PATTERN}`, 'gi');
     match = regex.exec(str);
     if (match) {
         obj.protocol = match[1].toLowerCase();

react/features/unsupported-browser/components/UnsupportedMobileBrowser.js

 
 import { translate, translateToHTML } from '../../base/i18n';
 import { Platform } from '../../base/react';
+import { URI_PROTOCOL_PATTERN } from '../../base/util';
 import { DialInSummary } from '../../invite';
 import HideNotificationBarStyle from './HideNotificationBarStyle';
 
         // appears to be a link with an app-specific scheme, not a Universal
         // Link.
         const appScheme = interfaceConfig.MOBILE_APP_SCHEME || 'org.jitsi.meet';
-        const joinURL = `${appScheme}:${window.location.href}`;
+
+        // Replace the protocol part with the app scheme.
+        const joinURL
+            = window.location.href.replace(
+                new RegExp(`^${URI_PROTOCOL_PATTERN}`), `${appScheme}:`);
 
         this.setState({
             joinURL