Warn when WebRTC isn't detected in the webext

Trac 31067

proxy/init-badge.coffee

@@ -2,6 +2,10 @@
 Entry point.
 ###
 
+if (not TESTING? or not TESTING) and not Util.featureDetect()
+  console.log 'webrtc feature not detected. shutting down'
+  return
+
 snowflake = null
 
 query = Query.parse(location)

proxy/init-webext.coffee

@@ -17,6 +17,12 @@ log = (msg) ->
 
 dbg = (msg) -> log msg if debug
 
+if not Util.featureDetect()
+  chrome.runtime.onConnect.addListener (port) ->
+    port.postMessage
+      missingFeature: true
+  return
+
 init = () ->
   config = new Config
   ui = new WebExtUI()

proxy/shims.coffee

@@ -31,9 +31,5 @@ else
   SessionDescription = window.RTCSessionDescription ||
     window.mozRTCSessionDescription
 
-  if typeof PeerConnection isnt 'function'
-    console.log 'webrtc feature not detected. shutting down'
-    return
-
   WebSocket = window.WebSocket
   XMLHttpRequest = window.XMLHttpRequest

proxy/util.coffee

@@ -34,6 +34,8 @@ class Util
       return true
     return false
 
+  @featureDetect = () ->
+    return typeof PeerConnection is 'function'
 
 class Query
   ###

proxy/webext/popup.js

@@ -3,11 +3,19 @@ const port = chrome.runtime.connect({
 });
 
 port.onMessage.addListener((m) => {
-  const active = m.active;
   const div = document.getElementById('active');
-  const img = div.querySelector('img');
-  const enabled = m.enabled
   const ps = div.querySelectorAll('p');
+  if (m.missingFeature) {
+    div.querySelector('img').src = "icons/status-off.png";
+    ps[0].innerText = "Snowflake is off";
+    ps[1].innerText = "WebRTC feature is not detected.";
+    ps[1].style.color = 'firebrick';
+    document.querySelector('.toggle').style.display = 'none';
+    return;
+  }
+  const active = m.active;
+  const img = div.querySelector('img');
+  const enabled = m.enabled;
   const clients = active ? 1 : 0;
   const enabledText = document.getElementById('toggle');
   if (enabled) {