Tests that setting selector text can be undone.

=== Before selector modification ===
[expanded] 
element.style { ()

[expanded] 
#inspected { (<style>)
    color: green;

[expanded] 
div { (user agent stylesheet)
    display: block;
    unicode-bidi: isolate;

=== After selector modification ===
[expanded] 
element.style { ()

[expanded] 
#inspected, #other { (<style>)
    color: green;

[expanded] 
div { (user agent stylesheet)
    display: block;
    unicode-bidi: isolate;

=== After undo ===
[expanded] 
element.style { ()

[expanded] 
#inspected { (<style>)
    color: green;

[expanded] 
div { (user agent stylesheet)
    display: block;
    unicode-bidi: isolate;

=== After redo ===
[expanded] 
element.style { ()

[expanded] 
#inspected, #other { (<style>)
    color: green;

[expanded] 
div { (user agent stylesheet)
    display: block;
    unicode-bidi: isolate;