Updates lib-jitsi-meet to d4b78721.

Implements the promised based getStats. Enables them for Safari and FF.

package-lock.json

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+    "js-utils": {
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+      "requires": {
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     "js-yaml": {
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       "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.7.0.tgz",
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     "lib-jitsi-meet": {
-      "version": "github:jitsi/lib-jitsi-meet#2184f328ed6d03de8c2be635cda402c895c183e5",
+      "version": "github:jitsi/lib-jitsi-meet#410ad5e76d33b1422ce34f83719eda7dfd584e22",
       "requires": {
         "async": "0.9.0",
         "current-executing-script": "0.1.3",
         "strophejs-plugin-disco": "0.0.2",
         "webrtc-adapter": "github:webrtc/adapter#1eec19782b4058d186341263e7d049cea3e3290a",
         "yaeti": "1.0.1"
-      },
-      "dependencies": {
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-        "js-utils": {
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     "load-json-file": {

package.json

     "jquery-i18next": "1.2.0",
     "js-md5": "0.6.1",
     "jwt-decode": "2.2.0",
-    "lib-jitsi-meet": "github:jitsi/lib-jitsi-meet#2184f328ed6d03de8c2be635cda402c895c183e5",
+    "lib-jitsi-meet": "github:jitsi/lib-jitsi-meet#410ad5e76d33b1422ce34f83719eda7dfd584e22",
     "lodash": "4.17.4",
     "moment": "2.19.4",
     "nuclear-js": "1.4.0",