ENH: Button to toggle view widget decorations

This button enables toggling visibility of widget decorations. The user can use
this button to hide view widget decorations to stage the scene for a faithful
screenshot.

This change fixes issue 14220

Change-Id: I167129272824da0c3ffa54bbe5277eaadc925ebd
Merge topic '14220-hide-decoration-button' into next

cec40878 ENH: Button to toggle view widget decorations