In MacViews, select text in the omnibox and drag it. You get:

2018-07-09 11:41:05.023 Chromium[6635:31609467] 'NSFilenamesPboardType' is not a valid UTI string.  Cannot set data provider for an invalid UTI.
2018-07-09 11:41:05.023 Chromium[6635:31609467] 'Apple HTML pasteboard type' is not a valid UTI string.  Cannot set data provider for an invalid UTI.
2018-07-09 11:41:05.023 Chromium[6635:31609467] 'Apple URL pasteboard type' is not a valid UTI string.  Cannot set data provider for an invalid UTI.
2018-07-09 11:41:05.023 Chromium[6635:31609467] 'NSStringPboardType' is not a valid UTI string.  Cannot set data provider for an invalid UTI.
2018-07-09 11:41:05.023 Chromium[6635:31609467] 'NeXT Rich Text Format v1.0 pasteboard type' is not a valid UTI string.  Cannot set data provider for an invalid UTI.

AppKit`+[NSPasteboard _isValidPasteboardUTI:logStringMessage:] + 279
AppKit`-[NSPasteboardItem setDataProvider:forTypes:] + 315
libviews.dylib`views::DragDropClientMac::StartDragAndDrop() + 815 at drag_drop_client_mac.mm:108
libviews.dylib`views::NativeWidgetMac::RunShellDrag() + 95 at native_widget_mac.mm:575
libviews.dylib`views::Widget::RunShellDrag() + 139 at widget.cc:792
libviews.dylib`views::View::DoDrag() + 437 at view.cc:2664
libviews.dylib`views::View::ProcessMouseDragged() + 368 at view.cc:2463
libviews.dylib`views::View::OnMouseEvent() + 185 at view.cc:1105

The MacViews drag code needs updating to new UTI APIs