Added sip protocol to sanitize html options (#2061)

* Added sip protocol

* Updated CHANGELOG.md

* insignificant change

CHANGELOG.md

@@ -47,6 +47,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 -  Fix [#1829](https://github.com/microsoft/BotFramework-WebChat/issues/1829). Fixed long text not being synthesized by Cognitive Services by bumping to [`[email protected]`](https://github.com/compulim/react-say), by [@compulim](https://github.com/compulim) in PR [#2035](https://github.com/Microsoft/BotFramework-WebChat/pull/2035)
 -  Fix [#1982](https://github.com/Microsoft/BotFramework-WebChat/issues/1982). Move to prettier! by [@corinagum](https://github.com/corinagum) in PR [#2038](https://github.com/Microsoft/BotFramework-WebChat/pull/2038)
 -  Fix [#1429](https://github.com/Microsoft/BotFramework-WebChat/issues/1429). Added markdown string preprocessing so the renderer will respect CRLF carriage returns (\r\n), by [@tdurnford](https://github.com/tdurnford) in PR [#2055](https://github.com/Microsoft/BotFramework-WebChat/pull/2055)
+-  Fix [#2057](https://github.com/Microsoft/BotFramework-WebChat/issues/2057). Added sip protocol to sanitize HTML options, by [@tdurnford](https://github.com/tdurnford) in PR [#2061](https://github.com/Microsoft/BotFramework-WebChat/pull/2061)
 
 ## [4.4.1] - 2019-05-02
 

packages/bundle/src/__tests__/renderMarkdown.spec.js

@@ -54,4 +54,11 @@ describe('renderMarkdown', () => {
       '<pre><code>{\n  "hello": "World!"\n}\n</code></pre>\n'
     );
   });
+
+  it('should render sip protocol links correctly', () => {
+    const styleSet = { options: { markdownRespectCRLF: true } };
+    expect(renderMarkdown(`[[email protected]](sip:[email protected])`, styleSet)).toBe(
+      '<p><a href="sip:[email protected]" target="_blank">[email protected]</a></p>\n'
+    );
+  });
 });

packages/bundle/src/renderMarkdown.js

@@ -9,6 +9,7 @@ const SANITIZE_HTML_OPTIONS = {
     a: ['href', 'name', 'target', 'title'],
     img: ['alt', 'src']
   },
+  allowedSchemes: ['http', 'https', 'ftp', 'mailto', 'sip'],
   allowedTags: [
     'a',
     'b',