Widget keSearchTrendingSearchphrases does not work in v12

[derhansen]

• The widget throws an exception when adding it to the dashboard. Reason for this is the widget registration in Services.php, where->arg('$backendViewFactory', new Reference(\TYPO3\CMS\Backend\View\BackendViewFactory::class)) is missing and ->arg('$view', new Reference('dashboard.views.widget')) should be removed. View usage is deprecated in v12.
• If the initial problem is fixed, the chart fails with an array to string conversion exception, because TrendingSearchphrasesDataProvider does not meet the return value requirements for ListDataProviderInterface (should be a simple list like ['item 1', 'item 2', 'item 3']). Obviously, there is no custom widget class available for this widget and therefore ext:dashboard widget class/template is used.