[gnome-shell/T27795: 135/138] baseAppView: Add new read-only id property

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 44c140ab82407f4a260ba3f354b35af9337c0962
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Mon Sep 30 22:54:38 2019 -0300

    baseAppView: Add new read-only id property
    
    This will be used by next commits to implement
    moving icon positions.

 js/ui/appDisplay.js | 10 ++++++++++
 1 file changed, 10 insertions(+)
---
diff --git a/js/ui/appDisplay.js b/js/ui/appDisplay.js
index 953bd4851b..2e4debb245 100644
--- a/js/ui/appDisplay.js
+++ b/js/ui/appDisplay.js
@@ -178,6 +178,8 @@ class BaseAppView {
 
         this._items = {};
         this._allItems = [];
+
+        this._id = null;
     }
 
     _childFocused(_actor) {
@@ -336,6 +338,10 @@ class BaseAppView {
     removeNudges() {
         this._grid.removeNudges();
     }
+
+    get id() {
+        return this._id;
+    }
 }
 Signals.addSignalMethods(BaseAppView.prototype);
 
@@ -392,6 +398,8 @@ var AllView = class AllView extends BaseAppView {
         this._stackBox = this.actor.stackBox;
         this._grid._delegate = this;
 
+        this._id = IconGridLayout.DESKTOP_GRID_ID;
+
         this._adjustment = this._scrollView.vscroll.adjustment;
 
         this._pageIndicators = new PageIndicators.AnimatedPageIndicators();
@@ -1108,6 +1116,8 @@ var FolderView = class FolderView extends BaseAppView {
 
         this._dirInfo = dirInfo;
 
+        this._id = dirInfo.get_id();
+
         // If it not expand, the parent doesn't take into account its preferred_width when allocating
         // the second time it allocates, so we apply the "Standard hack for ClutterBinLayout"
         this._grid.x_expand = true;