fix(IgxColumn): populate the visibleIndex correctly on show/hide mrl block #7390

Author: ddincheva

projects/igniteui-angular/src/lib/grids/columns/column-layout.component.ts

@@ -100,7 +100,12 @@ export class IgxColumnLayoutComponent extends IgxColumnGroupComponent implements
         this.children.forEach(child => child.hidden = value);
         if (this.grid && this.grid.columns && this.grid.columns.length > 0) {
             // reset indexes in case columns are hidden/shown runtime
-            this.grid.columns.filter(x => x.columnGroup).forEach(x => x.populateVisibleIndexes());
+            const columns = this.grid && this.grid.pinnedColumns && this.grid.unpinnedColumns ?
+            this.grid.pinnedColumns.concat(this.grid.unpinnedColumns) : [];
+            if (!this._hidden && !columns.find(c => c.field === this.field)) {
+                this.grid.resetColumnCollections();
+            }
+            this.grid.columns.filter(x => x.columnLayout).forEach(x => x.populateVisibleIndexes());
         }
     }