DialogBrowserTest implementation to invoke Content settings bubble dialogs.

chrome/browser/ui/content_settings/content_setting_image_model.h

Index: chrome/browser/ui/content_settings/content_setting_image_model.h
diff --git a/chrome/browser/ui/content_settings/content_setting_image_model.h b/chrome/browser/ui/content_settings/content_setting_image_model.h
index ded59c1681d84d78ee254c8a83433136f2e908d3..c6e16a35051e03cfd9d9dd3192d44fd0c85f1660 100644
--- a/chrome/browser/ui/content_settings/content_setting_image_model.h
+++ b/chrome/browser/ui/content_settings/content_setting_image_model.h
@@ -31,6 +31,11 @@ class ContentSettingImageModel {
   static std::vector<std::unique_ptr<ContentSettingImageModel>>
   GenerateContentSettingImageModels();
 
+  // Returns the corresponding index into the above vector for the given
+  // ContentSettingsType. For testing.
+  static size_t GetContentSettingImageModelIndexForTesting(
+      ContentSettingsType content_type);
+
   // Notifies this model that its setting might have changed and it may need to
   // update its visibility, icon and tooltip.
   virtual void UpdateFromWebContents(content::WebContents* web_contents) = 0;