fix: ensure `WebContents` before checking draggable region (#41154)

fix: ensure WebContents before checking draggable region

shell/browser/api/electron_api_web_contents_view.cc

@@ -81,11 +81,14 @@ void WebContentsView::SetBackgroundColor(std::optional<WrappedSkColor> color) {
 }
 
 int WebContentsView::NonClientHitTest(const gfx::Point& point) {
+  if (api_web_contents_) {
     gfx::Point local_point(point);
     views::View::ConvertPointFromWidget(view(), &local_point);
     SkRegion* region = api_web_contents_->draggable_region();
     if (region && region->contains(local_point.x(), local_point.y()))
       return HTCAPTION;
+  }
+
   return HTNOWHERE;
 }