[Layout] Add JSDoc to new scripts

Add in-line documentation to new scripts introduced to
support the transitioned Layout view, WTD-535.

platform/representation/src/gestures/GestureRepresenter.js

@@ -5,10 +5,23 @@ define(
     function () {
         "use strict";
 
+        /**
+         * The GestureRepresenter is responsible for installing predefined
+         * gestures upon mct-representation instances.
+         * Gestures themselves are pulled from the gesture service; this
+         * simply wraps that behavior in a Representer interface, such that
+         * it may be included among other such Representers used to prepare
+         * specific representations.
+         * @param {GestureService} gestureService the service which provides
+         *        gestures
+         * @param {Scope} scope the Angular scope for this representation
+         * @param element the JQLite-wrapped mct-representation element
+         */
         function GestureRepresenter(gestureService, scope, element) {
             var gestureHandle;
 
             function destroy() {
+                // Release any resources associated with these gestures
                 if (gestureHandle) {
                     gestureHandle.destroy();
                 }
@@ -27,7 +40,19 @@ define(
             }
 
             return {
+                /**
+                 * Set the current representation in use, and the domain
+                 * object being represented.
+                 *
+                 * @param {RepresentationDefinition} representation the
+                 *        definition of the representation in use
+                 * @param {DomainObject} domainObject the domain object
+                 *        being represented
+                 */
                 represent: represent,
+                /**
+                 * Release any resources associated with this representer.
+                 */
                 destroy: destroy
             };
         }