add modal plugin interface; optimize layouts code

doric-Qt/doric/plugin/DoricModalPlugin.cpp

@@ -0,0 +1,5 @@
+#include "DoricModalPlugin.h"
+
+void DoricModalPlugin::toast(QString jsValueString, QString callbackId) {
+  qDebug() << "toast";
+}

doric-Qt/doric/plugin/DoricModalPlugin.h

@@ -0,0 +1,14 @@
+#ifndef DORICMODALPLUGIN_H
+#define DORICMODALPLUGIN_H
+
+#include "DoricNativePlugin.h"
+
+class DoricModalPlugin : public DoricNativePlugin {
+  Q_OBJECT
+public:
+  using DoricNativePlugin::DoricNativePlugin;
+
+  Q_INVOKABLE void toast(QString jsValueString, QString callbackId);
+};
+
+#endif // DORICMODALPLUGIN_H

doric-Qt/doric/plugin/DoricShaderPlugin.h

@@ -1,9 +1,6 @@
 #ifndef SHADERPLUGIN_H
 #define SHADERPLUGIN_H
 
-#include <QJSValue>
-#include <QObject>
-
 #include "DoricNativePlugin.h"
 
 class DoricShaderPlugin : public DoricNativePlugin {