[eslint] arrow-body-style

.eslintrc.js

         'wrap-regex': 0,
 
         // ES6 group rules
+        'arrow-body-style': [
+            'error',
+            'as-needed',
+            { requireReturnForObjectLiteral: true }
+        ],
         'arrow-parens': [ 'error', 'as-needed' ],
         'arrow-spacing': 2,
         'constructor-super': 2,

JitsiConference.js

                 this._setupNewTrack(newTrack);
             }
             return Promise.resolve();
-        }, error => {
-            return Promise.reject(new Error(error));
-        });
+        }, error => Promise.reject(new Error(error)));
 };
 
 /**

modules/RTC/RTC.js

         let tracks = this.localTracks.slice();
         if (mediaType !== undefined) {
             tracks = tracks.filter(
-                track => {
-                    return track.getType() === mediaType; 
-                });
+                track => track.getType() === mediaType);
         }
         return tracks;
     }
      */
     getResourceBySSRC (ssrc) {
         if (this.getLocalTracks().find(
-                localTrack => {
-                    return localTrack.getSSRC() == ssrc; 
-                })) {
+                localTrack => localTrack.getSSRC() == ssrc)) {
             return this.conference.myUserId();
         }
 

modules/xmpp/Caps.js

         const features = this.disco._features.sort();
         this.version = b64_sha1(
             identities.reduce(
-                (accumulatedValue, identity) => {
-                    return IDENTITY_PROPERTIES.reduce((tmp, key, idx) => {
-                        return tmp + (idx === 0 ? "" : "/") + identity[key];
-                    }, "") + "<";
-                }, ""
-            ) + features.reduce((tmp, feature) => tmp + feature + "<", "")
-        );
+                    (accumulatedValue, identity) =>
+                        IDENTITY_PROPERTIES.reduce(
+                                (tmp, key, idx) =>
+                                    tmp
+                                        + (idx === 0 ? "" : "/")
+                                        + identity[key],
+                                "")
+                            + "<",
+                    "")
+                + features.reduce((tmp, feature) => tmp + feature + "<", ""));
         this._notifyVersionChanged();
     }
 

modules/xmpp/SdpTransformUtil.js

      */
     containsSSRC(ssrcNumber) {
         return !!this._ssrcs.find(
-            ssrcObj => {
-                return ssrcObj.id == ssrcNumber; 
-            });
+            ssrcObj => ssrcObj.id == ssrcNumber);
     }
 
     /**