NetInfo network quality extension: Add callbacks and Layout tests

third_party/WebKit/LayoutTests/netinfo/resources/netinfo_common.js

 window.jsTestIsAsync = true;
 
 var connection = navigator.connection;
 var initialType = "bluetooth";
 var initialDownlinkMax = 1.0;
 var newConnectionType = "ethernet";
 var newDownlinkMax = 2.0;
+var initialEffectiveType = "3g";
+var initialRtt = 25.0;
+var initialDownlink = 10.0;
+var newEffectiveType = "4g";
+var newRtt = 50.0;
+var newDownlink = 30.0;
 
 // Suppress connection messages information from the host.
 if (window.internals) {
     internals.setNetworkConnectionInfoOverride(true, initialType, initialDownlinkMax);
+    internals.setNetworkQualityInfoOverride(initialEffectiveType, initialRtt, initialDownlink);
 
     // Reset the state of the singleton network state notifier.
     window.addEventListener('beforeunload', function() {
         internals.clearNetworkConnectionInfoOverride();
     }, false);
 }
 
 function isTypeOnline(type) {
     return type != 'none';
 }