Tests that adding a property is undone properly.

=== Last property ===
(Initial value)
[expanded] 
element.style  { ()

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
font-weight: bold;

[expanded] 
div  { (user agent stylesheet)
display: block;


(After adding property)
[expanded] 
element.style  { ()

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


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

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
font-weight: bold;

[expanded] 
div  { (user agent stylesheet)
display: block;


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

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


=== First property ===
(Initial value)
[expanded] 
element.style  { ()

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


(After adding property)
[expanded] 
element.style  { ()

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
margin-top: 0px;
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


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

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


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

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
margin-top: 0px;
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


=== Middle property ===
(Initial value)
[expanded] 
element.style  { ()

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
margin-top: 0px;
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


(After adding property)
[expanded] 
element.style  { ()

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
margin-top: 0px;
margin-right: 1px;
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


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

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
margin-top: 0px;
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;


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

======== Matched CSS Rules ========
[expanded] 
.container  { (undo-add-property.html:7)
margin-top: 0px;
margin-right: 1px;
font-weight: bold;
margin-left: 2px;

[expanded] 
div  { (user agent stylesheet)
display: block;