[css-display-3] Remove outdated display: contents test.

The flex spec was updated a while ago to use the following language for
align-items:

> align-items sets the default alignment for all of the flex container’s items,
> including anonymous flex items. align-self allows this default alignment to
> be overridden for individual flex items.

After that, the CSSWG resolved that align-self: auto computes to itself[1][2].

Thus, this test is invalid.

[1]: w3c/csswg-drafts#440 (comment)
[2]: https://lists.w3.org/Archives/Public/www-style/2016Sep/0041.html

css-display-3/display-contents-computed-style.html

@@ -15,11 +15,7 @@
 
     #t3 .contents { color: green }
 
-    #t4 { display: flex; align-items: center }
-    #t4 .contents { align-items: baseline }
-    #t4 span { align-self: auto }
-
-    #t5 {
+    #t4 {
         width: auto;
         height: 50%;
         margin-left: 25%;
@@ -42,7 +38,7 @@
         <span></span>
     </div>
 </div>
-<div id="t5" class="contents"></div>
+<div id="t4" class="contents"></div>
 <script>
     test(function(){
         assert_equals(getComputedStyle(document.querySelector("#t1")).display, "contents");
@@ -57,11 +53,7 @@
     }, "display:contents element as inherit parent - implicit inheritance");
 
     test(function(){
-        assert_equals(getComputedStyle(document.querySelector("#t4 span")).alignSelf, "baseline");
-    }, "align-self:auto resolution for flex item inside display:contents");
-
-    test(function(){
-        var computed = getComputedStyle(document.querySelector("#t5"));
+        var computed = getComputedStyle(document.querySelector("#t4"));
         assert_equals(computed.width, "auto");
         assert_equals(computed.height, "50%");
         assert_equals(computed.marginLeft, "25%");