Adding removeColumns() and removeRows() to GridLayout

ui/layouts/grid-layout/grid-layout-common.ts

@@ -202,6 +202,22 @@ export class GridLayout extends layouts.LayoutBase implements definition.GridLay
         this.onColumnRemoved(itemSpec, index);
     }
 
+    public removeColumns() {
+        for (var i = 0; i < this._cols.length; i++) {
+            this._cols[i].index = -1;
+        }
+        this._cols.length = 0;
+        this.invalidate();
+    }
+
+    public removeRows() {
+        for (var i = 0; i < this._rows.length; i++) {
+            this._rows[i].index = -1;
+        }
+        this._rows.length = 0;
+        this.invalidate();
+    }
+
     protected onRowChanged(element: view.View, oldValue: number, newValue: number) {
         //
     }

ui/layouts/grid-layout/grid-layout.d.ts

@@ -131,11 +131,21 @@
          */
         public removeColumn(itemSpec: ItemSpec): void;
 
+        /**
+         * Removes all columns specification from a GridLayout.
+         */
+        removeColumns(): void;
+
         /**
          * Removes a row specification from a GridLayout.
          */
         public removeRow(itemSpec: ItemSpec): void;
 
+        /**
+         * Removes all rows specification from a GridLayout.
+         */
+        removeRows(): void;
+
         /**
          * Gets array of column specifications defined on this instance of GridLayout. 
          */