Add miniPaint as new frontend base

frontend/src/js/actions/prepare-canvas.js

@@ -0,0 +1,29 @@
+import app from '../app.js';
+import config from '../config.js';
+import { Base_action } from './base.js';
+
+export class Prepare_canvas_action extends Base_action {
+	/**
+	 * Resizes/renders the canvas at the specified step. Usually used on both sides of a config update action.
+	 *
+	 * @param {boolean} call_when
+	 */
+	constructor(call_when = 'undo') {
+		super('prepare_canvas', 'Prepare Canvas');
+		this.call_when = call_when;
+	}
+
+	async do() {
+		super.do();
+		if (this.call_when === 'do') {
+			app.GUI.prepare_canvas();
+		}
+	}
+
+	async undo() {
+		super.undo();
+		if (this.call_when === 'undo') {
+			app.GUI.prepare_canvas();
+		}
+	}
+}