Move the GenericScripting class to its own file, such that it can be used in the Chromium-extension

While it's not entirely clear to me that it's ultimately desirable to use the `pdf.sandbox.js` in the Chromium-extension, given that the MOZCENTRAL-build uses `pdf.scripting.js` directly in a *custom* sandbox, the current state isn't that great since setting `enableScripting = true` with the Chromium-extension will currently fail completely.

Hence this patch, which should at least unbreak things for now.

web/app_options.js

@@ -265,6 +265,12 @@ if (
         : "../build/pdf.sandbox.js",
     kind: OptionKind.VIEWER,
   };
+} else if (PDFJSDev.test("CHROME")) {
+  defaultOptions.sandboxBundleSrc = {
+    /** @type {string} */
+    value: "../build/pdf.sandbox.js",
+    kind: OptionKind.VIEWER,
+  };
 }
 
 const userOptions = Object.create(null);

web/chromecom.js

@@ -19,6 +19,7 @@ import { AppOptions } from "./app_options.js";
 import { BasePreferences } from "./preferences.js";
 import { DownloadManager } from "./download_manager.js";
 import { GenericL10n } from "./genericl10n.js";
+import { GenericScripting } from "./generic_scripting.js";
 
 if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("CHROME")) {
   throw new Error(
@@ -428,6 +429,10 @@ class ChromeExternalServices extends DefaultExternalServices {
   static createL10n(options) {
     return new GenericL10n(navigator.language);
   }
+
+  static get scripting() {
+    return new GenericScripting();
+  }
 }
 PDFViewerApplication.externalServices = ChromeExternalServices;
 

web/generic_scripting.js

@@ -0,0 +1,45 @@
+/* Copyright 2020 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { AppOptions } from "./app_options.js";
+import { loadScript } from "pdfjs-lib";
+
+class GenericScripting {
+  constructor() {
+    this._ready = loadScript(
+      AppOptions.get("sandboxBundleSrc"),
+      /* removeScriptElement = */ true
+    ).then(() => {
+      return window.pdfjsSandbox.QuickJSSandbox();
+    });
+  }
+
+  async createSandbox(data) {
+    const sandbox = await this._ready;
+    sandbox.create(data);
+  }
+
+  async dispatchEventInSandbox(event) {
+    const sandbox = await this._ready;
+    sandbox.dispatchEvent(event);
+  }
+
+  async destroySandbox() {
+    const sandbox = await this._ready;
+    sandbox.nukeSandbox();
+  }
+}
+
+export { GenericScripting };

web/genericcom.js

@@ -14,11 +14,10 @@
  */
 
 import { DefaultExternalServices, PDFViewerApplication } from "./app.js";
-import { AppOptions } from "./app_options.js";
 import { BasePreferences } from "./preferences.js";
 import { DownloadManager } from "./download_manager.js";
 import { GenericL10n } from "./genericl10n.js";
-import { loadScript } from "pdfjs-lib";
+import { GenericScripting } from "./generic_scripting.js";
 
 if (typeof PDFJSDev !== "undefined" && !PDFJSDev.test("GENERIC")) {
   throw new Error(
@@ -39,32 +38,6 @@ class GenericPreferences extends BasePreferences {
   }
 }
 
-class GenericScripting {
-  constructor() {
-    this._ready = loadScript(
-      AppOptions.get("sandboxBundleSrc"),
-      /* removeScriptElement = */ true
-    ).then(() => {
-      return window.pdfjsSandbox.QuickJSSandbox();
-    });
-  }
-
-  async createSandbox(data) {
-    const sandbox = await this._ready;
-    sandbox.create(data);
-  }
-
-  async dispatchEventInSandbox(event) {
-    const sandbox = await this._ready;
-    sandbox.dispatchEvent(event);
-  }
-
-  async destroySandbox() {
-    const sandbox = await this._ready;
-    sandbox.nukeSandbox();
-  }
-}
-
 class GenericExternalServices extends DefaultExternalServices {
   static createDownloadManager(options) {
     return new DownloadManager();