[Fixed Position] Add stroke property

Add stroke property to Fixed Position toolbar for
borders, line color. WTD-881.

platform/features/layout/src/elements/ElementFactory.js

@@ -6,20 +6,24 @@ define(
         "use strict";
 
         var INITIAL_STATES = {
-                "fixed.image": {},
+                "fixed.image": {
+                    stroke: "transparent"
+                },
                 "fixed.box": {
-                    fill: "#888",
-                    border: "transparent"
+                    fill: "#717171",
+                    border: "transparent",
+                    stroke: "transparent"
                 },
                 "fixed.line": {
                     x: 5,
                     y: 9,
                     x2: 6,
-                    y2: 6
+                    y2: 6,
+                    stroke: "#717171"
                 },
                 "fixed.text": {
                     fill: "transparent",
-                    border: "transparent"
+                    stroke: "transparent"
                 }
             },
             DIALOGS = {

platform/features/layout/src/elements/ElementProxy.js

@@ -49,11 +49,11 @@ define(
                  */
                 y: new AccessorMutator(element, 'y'),
                 /**
-                 * Get and/or set the z index of this element.
-                 * @param {number} [z] the new z index (if setting)
-                 * @returns {number} the z index
+                 * Get and/or set the stroke color of this element.
+                 * @param {string} [stroke] the new stroke color (if setting)
+                 * @returns {string} the stroke color
                  */
-                z: new AccessorMutator(element, 'z'),
+                stroke: new AccessorMutator(element, 'stroke'),
                 /**
                  * Get and/or set the width of this element.
                  * Units are in fixed position grid space.