Add PopupVoid (#734)

ext/fg/js/popup-void.js

@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2020  Yomichan Authors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/**
+ * A void popup with no functionality, usable as a placeholder.
+ */
+class PopupVoid {
+    constructor(id, depth, frameId, ownerFrameId) {
+        this._id = id;
+        this._depth = depth;
+        this._frameId = frameId;
+        this._ownerFrameId = ownerFrameId;
+        this._parent = null;
+        this._child = null;
+    }
+
+    // Public properties
+
+    get id() {
+        return this._id;
+    }
+
+    get parent() {
+        return this._parent;
+    }
+
+    set parent(value) {
+        this._parent = value;
+    }
+
+    get child() {
+        return this._child;
+    }
+
+    set child(value) {
+        this._child = value;
+    }
+
+    get depth() {
+        return this._depth;
+    }
+
+    get frameContentWindow() {
+        return null;
+    }
+
+    get container() {
+        return null;
+    }
+
+    // Public functions
+
+    prepare() {
+        // NOP
+    }
+
+    async setOptionsContext(_optionsContext, _source) {
+        // NOP
+    }
+
+    hide(_changeFocus) {
+        // NOP
+    }
+
+    async isVisible() {
+        return false;
+    }
+
+    setVisibleOverride(_visible) {
+        // NOP
+    }
+
+    async containsPoint(_x, _y) {
+        return false;
+    }
+
+    async showContent(_details, _displayDetails) {
+        // NOP
+    }
+
+    setCustomCss(_css) {
+        // NOP
+    }
+
+    clearAutoPlayTimer() {
+        // NOP
+    }
+
+    setContentScale(_scale) {
+        // NOP
+    }
+
+    isVisibleSync() {
+        return false;
+    }
+
+    updateTheme() {
+        // NOP
+    }
+
+    async setCustomOuterCss(_css, _useWebExtensionApi) {
+        return null;
+    }
+
+    setChildrenSupported(_value) {
+        // NOP
+    }
+
+    getFrameRect() {
+        return new DOMRect(0, 0, 0, 0);
+    }
+}