Add support for tel: links in captive portal app.

Bug:21447011
Change-Id: I72ec4fd780ddb89cecfa584aa285f3822f326810
diff --git a/packages/CaptivePortalLogin/src/com/android/captiveportallogin/CaptivePortalLoginActivity.java b/packages/CaptivePortalLogin/src/com/android/captiveportallogin/CaptivePortalLoginActivity.java
index d876264..d00f850 100644
--- a/packages/CaptivePortalLogin/src/com/android/captiveportallogin/CaptivePortalLoginActivity.java
+++ b/packages/CaptivePortalLogin/src/com/android/captiveportallogin/CaptivePortalLoginActivity.java
@@ -342,6 +342,15 @@
                     getString(R.string.ssl_error_continue));
             view.loadDataWithBaseURL(INTERNAL_ASSETS, html, "text/HTML", "UTF-8", null);
         }
+
+        @Override
+        public boolean shouldOverrideUrlLoading (WebView view, String url) {
+            if (url.startsWith("tel:")) {
+                startActivity(new Intent(Intent.ACTION_DIAL, Uri.parse(url)));
+                return true;
+            }
+            return false;
+        }
     }
 
     private class MyWebChromeClient extends WebChromeClient {