when touched, rows using 'x-mojo-touch-feedback' will display a selection graphic implemented using -webkit-border-image with a 9-tile image (minimum 41 x 49 px)
three types of feedback
delayed
immediate
delayedPersistent
immediatePersistent
For elements within scrollable content, use "delayed" feedback. (This prevents erroneous display and flickering of touch feedback while dragging/scrolling a list of touchable elements.)
For fixed elements which don't scroll, like elements in fixed headers or dialog panels, "immediate" feedback will display without delay.
Only use "delayedPersistent" and "immediatePersistent" feedback if you need to control the removal of touch feedback. Note that subsequent touch feedback on other elements will automatically remove existing feedback.