Add initial touch bar specs

lib/browser/api/touch-bar.js

@@ -24,7 +24,7 @@ class TouchBar extends EventEmitter {
     super()
 
     if (!Array.isArray(items)) {
-      throw new Error('The items object provided has to be an array')
+      throw new Error('Must specify items array as first argument')
     }
 
     this.windowListeners = {}
@@ -42,7 +42,7 @@ class TouchBar extends EventEmitter {
     }
     items.forEach((item) => {
       if (!(item instanceof TouchBarItem)) {
-        throw new Error('Each item must be an instance of a TouchBarItem')
+        throw new Error('Each item must be an instance of TouchBarItem')
       }
       this.ordereredItems.push(item)
       registerItem(item)
@@ -121,7 +121,9 @@ TouchBar.TouchBarButton = class TouchBarButton extends TouchBarItem {
     this._addLiveProperty('backgroundColor', backgroundColor)
     this._addLiveProperty('icon', icon)
     if (typeof click === 'function') {
-      this.onInteraction = config.click
+      this.onInteraction = () => {
+        config.click()
+      }
     }
   }
 }