feat: add disableDialogs option to WebPreferences (#22664)

Allows to disable dialogs completely in a similar way of how safeDialogs option can be used. Overrides safeDialogs option.

docs/api/browser-window.md

@@ -369,6 +369,8 @@ It creates a new `BrowserWindow` with native properties as set by the `options`.
       consecutive dialog protection is triggered. If not defined the default
       message would be used, note that currently the default message is in
       English and not localized.
+    * `disableDialogs` Boolean (optional) - Whether to disable dialogs
+      completely. Overrides `safeDialogs`. Default is `false`.
     * `navigateOnDragDrop` Boolean (optional) - Whether dragging and dropping a
       file or link onto the page causes a navigation. Default is `false`.
     * `autoplayPolicy` String (optional) - Autoplay policy to apply to

shell/browser/electron_javascript_dialog_manager.cc

@@ -61,6 +61,12 @@ void ElectronJavaScriptDialogManager::RunJavaScriptDialog(
     return;
   }
 
+  auto* web_preferences = WebContentsPreferences::From(web_contents);
+
+  if (web_preferences && web_preferences->IsEnabled("disableDialogs")) {
+    return std::move(callback).Run(false, base::string16());
+  }
+
   // No default button
   int default_id = -1;
   int cancel_id = 0;
@@ -75,7 +81,6 @@ void ElectronJavaScriptDialogManager::RunJavaScriptDialog(
 
   origin_counts_[origin]++;
 
-  auto* web_preferences = WebContentsPreferences::From(web_contents);
   std::string checkbox;
   if (origin_counts_[origin] > 1 && web_preferences &&
       web_preferences->IsEnabled("safeDialogs") &&