Getting net::ERR_UNKNOWN_URL_SCHEME while calling telephone number from HTML page in Android

I am getting "net::ERR_UNKNOWN_URL_SCHEME" while calling a telephone number option from an HTML page in Android. Do I need to add any permission(s) in the manifest to get this working? I haven't added anything in the manifest so far. Here's the HTML Code:

<a
href="tel:+1800229933">Call us free!</a>

The following should work and not require any permissions in the manifest (basically override shouldOverrideUrlLoading and handle
links separately from tel, mailto, etc.):

mWebView = (WebView) findViewById(R.id.web_view);

    WebSettings webSettings = mWebView.getSettings();
    webSettings.setJavaScriptEnabled(true);

    mWebView.setWebViewClient(new WebViewClient(){
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            if( url.startsWith("http:") || url.startsWith("https:") ) {
                return false;
            }

            // Otherwise allow the OS to handle things like tel, mailto, etc.
            Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
            startActivity( intent );
            return true;
        }
    });
    mWebView.loadUrl(url);