Bug 1456887 part 1. Remove the [ArrayClass] annotation from DOMRectList. r=qdot

The NoInterfaceObject bit is me cleaning up after spec editors who change the
spec without updating the tests...

dom/tests/mochitest/general/test_clientRects.html

@@ -29,11 +29,8 @@ function doc(id) {
 function checkElement(id, list, eps, doc) {
   var e = (doc || document).getElementById(id);
   var clientRects = e.getClientRects();
-  ok(clientRects instanceof e.ownerDocument.defaultView.Array,
-     "getClientRects retval should have Array.prototype on its proto chain");
-  clientRects.map(function(rect) {
-    ok(rect instanceof DOMRect, "Should have a DOMRect here");
-  });
+  ok(!(clientRects instanceof e.ownerDocument.defaultView.Array),
+     "getClientRects retval should not have Array.prototype on its proto chain");
   is(clientRects.length, list.length, "getClientRects().length for element '" + id + "'");
   var bounds = list.length > 0 ? list[0] : [0,0,0,0];
   for (var i = 0; i < clientRects.length && i < list.length; ++i) {

dom/webidl/DOMRectList.webidl

@@ -4,7 +4,6 @@
  * You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-[ArrayClass]
 interface DOMRectList {
   readonly attribute unsigned long length;
   getter DOMRect? item(unsigned long index);

testing/web-platform/meta/css/geometry/DOMRectList.html.ini

@@ -1,4 +0,0 @@
-[DOMRectList.html]
-  [DOMRectList [NoInterfaceObject\]]
-    expected: FAIL
-

testing/web-platform/tests/css/geometry/DOMRectList.html

@@ -10,12 +10,12 @@ setup(() => {
 });
 
 test(() => {
-  assert_false('DOMRectList' in window);
-}, 'DOMRectList [NoInterfaceObject]');
+  assert_true('DOMRectList' in window);
+}, 'DOMRectList is not [NoInterfaceObject]');
 
 test(() => {
-  assert_true(domRectList instanceof Array);
-}, 'DOMRectList [LegacyArrayClass]');
+  assert_false(domRectList instanceof Array);
+}, 'DOMRectList is not [LegacyArrayClass]');
 
 test(() => {
   assert_equals(domRectList.length, 1);