Bug 1299286 - Add the touchdownstartsdrag attribute to customize mode elements. r=jaws

MozReview-Commit-ID: LziDBjACA0

--HG--
extra : rebase_source : b0c08cb1ecafa6fce4b9e55ce3dae65412c5070e

browser/components/customizableui/CustomizeMode.jsm

@@ -904,6 +904,12 @@ CustomizeMode.prototype = {
     let removable = aPlace == "palette" || CustomizableUI.isWidgetRemovable(aNode);
     wrapper.setAttribute("removable", removable);
 
+    if (AppConstants.platform == "win") {
+      // Allow touch events to initiate dragging in customize mode.
+      // This is only supported on Windows for now.
+      wrapper.setAttribute("touchdownstartsdrag", "true");
+    }
+
     let contextMenuAttrName = "";
     if (aNode.getAttribute("context")) {
       contextMenuAttrName = "context";