Reg->5.12 Beta3 Quicknanobrowser ASSERTS before the UI was shown, because of call on wrong thread

Quicknanobrowser asserts in weak_ptr.cc after call to content::RenderWidgetHostImpl::SynchronizeVisualProperties from QtWebEngineCore::RenderWidgetHostViewQt::updatePaintNode was made on the wrong thread (i.e. the SGRenderThread when it should have been CrBrowserMain).

Simplebrowser works fine as the calls are all made on the CrBrowserMain thread.