Remove remaining uses of query-string with URLSearchParams

Replace remaining use of query-string dependency with the
URLSearchParams browser API. This will allow us to remove the
dependency.

src/sidebar/config/host-config.js

-import * as queryString from 'query-string';
 import {
   toBoolean,
   toInteger,
@@ -16,7 +15,7 @@ import {
  */
 export default function hostPageConfig(window) {
   const configStr = window.location.hash.slice(1);
-  const configJSON = queryString.parse(configStr).config;
+  const configJSON = new URLSearchParams(configStr).get('config');
   const config = JSON.parse(configJSON || '{}');
 
   // Known configuration parameters which we will import from the host page.

src/sidebar/services/router.js

-import * as queryString from 'query-string';
-
 /**
  * @typedef {'annotation'|'notebook'|'stream'|'sidebar'} RouteName
  * @typedef {Record<string,string>} RouteParams
@@ -29,7 +27,13 @@ export class RouterService {
   currentRoute() {
     const path = this._window.location.pathname;
     const pathSegments = path.slice(1).split('/');
-    const params = queryString.parse(this._window.location.search);
+    const searchParams = new URLSearchParams(this._window.location.search);
+
+    /** @type {Record<string, string>} */
+    const params = {};
+    for (let [key, value] of searchParams) {
+      params[key] = value;
+    }
 
     // The extension puts client resources under `/client/` to separate them
     // from extension-specific resources. Ignore this part.
@@ -94,9 +98,15 @@ export class RouterService {
         throw new Error(`Cannot generate URL for route "${name}"`);
     }
 
-    const query = queryString.stringify(queryParams);
-    if (query.length > 0) {
-      url += '?' + query;
+    let hasParams = false;
+    const searchParams = new URLSearchParams();
+    for (let [key, value] of Object.entries(queryParams)) {
+      hasParams = true;
+      searchParams.set(key, value);
+    }
+
+    if (hasParams) {
+      url += '?' + searchParams.toString();
     }
 
     return url;

src/sidebar/services/streamer.js

-import * as queryString from 'query-string';
-
 import warnOnce from '../../shared/warn-once';
 import { generateHexString } from '../util/random';
 import { Socket } from '../websocket';
@@ -190,9 +188,7 @@ export class StreamerService {
       // not support setting the `Authorization` header directly as we do for
       // other API requests.
       const parsedURL = new URL(this._websocketURL);
-      const queryParams = queryString.parse(parsedURL.search);
-      queryParams.access_token = token;
-      parsedURL.search = queryString.stringify(queryParams);
+      parsedURL.searchParams.set('access_token', token);
       url = parsedURL.toString();
     } else {
       url = this._websocketURL;

src/sidebar/services/test/streamer-test.js

@@ -211,7 +211,7 @@ describe('StreamerService', () => {
       return activeStreamer.connect().then(() => {
         assert.equal(
           fakeWebSocket.url,
-          'ws://example.com/ws?access_token=dummy-access-token&foo=bar'
+          'ws://example.com/ws?foo=bar&access_token=dummy-access-token'
         );
       });
     });