Fix Promise.defer warnings in index.js (element-hq#7409)

Signed-off-by: Aaron Raimist <aaron@raim.ist>

src/vector/index.js

@@ -179,37 +179,35 @@ function makeRegistrationUrl(params) {
 }
 
 function getConfig(configJsonFilename) {
-    let deferred = Promise.defer();
-
-    request(
-        { method: "GET", url: configJsonFilename },
-        (err, response, body) => {
-            if (err || response.status < 200 || response.status >= 300) {
-                // Lack of a config isn't an error, we should
-                // just use the defaults.
-                // Also treat a blank config as no config, assuming
-                // the status code is 0, because we don't get 404s
-                // from file: URIs so this is the only way we can
-                // not fail if the file doesn't exist when loading
-                // from a file:// URI.
-                if (response) {
-                    if (response.status == 404 || (response.status == 0 && body == '')) {
-                        deferred.resolve({});
+    return new Promise(function(resolve, reject) {
+        request(
+            { method: "GET", url: configJsonFilename },
+            (err, response, body) => {
+                if (err || response.status < 200 || response.status >= 300) {
+                    // Lack of a config isn't an error, we should
+                    // just use the defaults.
+                    // Also treat a blank config as no config, assuming
+                    // the status code is 0, because we don't get 404s
+                    // from file: URIs so this is the only way we can
+                    // not fail if the file doesn't exist when loading
+                    // from a file:// URI.
+                    if (response) {
+                        if (response.status == 404 || (response.status == 0 && body == '')) {
+                            resolve({});
+                        }
                     }
+                    reject({err: err, response: response});
+                    return;
                 }
-                deferred.reject({err: err, response: response});
-                return;
-            }
-
-            // We parse the JSON ourselves rather than use the JSON
-            // parameter, since this throws a parse error on empty
-            // which breaks if there's no config.json and we're
-            // loading from the filesystem (see above).
-            deferred.resolve(JSON.parse(body));
-        }
-    );
 
-    return deferred.promise;
+                // We parse the JSON ourselves rather than use the JSON
+                // parameter, since this throws a parse error on empty
+                // which breaks if there's no config.json and we're
+                // loading from the filesystem (see above).
+                resolve(JSON.parse(body));
+            }
+        );
+    })
 }
 
 function onTokenLoginCompleted() {