Move getFriendlyDisplayName to RoomMember class. Add more utlity functions.

lib/models/room-state.js

@@ -2,6 +2,7 @@
 /**
  * @module models/room-state
  */
+var utils = require("../utils");
 
 /**
  * Construct room state.
@@ -21,6 +22,28 @@ function RoomState() {
     };
     this.paginationToken = null;
 }
+RoomState.prototype = {
+    /**
+     * Get state events from the state of the room.
+     * @param {string} eventType The event type of the state event.
+     * @param {string} stateKey Optional. The state_key of the state event. If
+     * this is <code>undefined</code> then all matching state events will be
+     * returned.
+     * @return {MatrixEvent[]|MatrixEvent} A list of events if state_key was
+     * <code>undefined</code>, else a single event (or null if no match found).
+     */
+    getStateEvents: function(eventType, stateKey) {
+        if (!this.stateEvents[eventType]) {
+            // no match
+            return stateKey ? null : [];
+        }
+        if (!stateKey) { // return all values
+            return utils.values(this.stateEvents[eventType]);
+        }
+        var event = this.stateEvents[eventType][stateKey];
+        return event ? event : null;
+    }
+};
 
 /**
  * The RoomState class.