Add observers for stylesheet mutations (#177)

* hack together stylesheet observer

* Add test coverage for insertRule/deleteRule on stylesheets

* Add new observers

* update patch based on changes to master

* Functioning event recording

* Remove print statements

* Fix ID usage and mark add vs remove

* Correct type

Co-authored-by: Jon Perl <perl.jonathan@gmail.com>

test/replayer.test.ts

@@ -12,6 +12,7 @@ import {
   MouseInteractions,
 } from '../src/types';
 import { Replayer } from '../src';
+import { launchPuppeteer } from './utils';
 
 const now = Date.now();
 
@@ -122,10 +123,7 @@ interface ISuite extends Suite {
 
 describe('replayer', function(this: ISuite) {
   before(async () => {
-    this.browser = await puppeteer.launch({
-      headless: false,
-      args: ['--no-sandbox'],
-    });
+    this.browser = await launchPuppeteer();
 
     const bundlePath = path.resolve(__dirname, '../dist/rrweb.min.js');
     this.code = fs.readFileSync(bundlePath, 'utf8');