[NGFragmentItem] Ignore NGInlineFragmentTraversalTest for NGFragmentItem

This patch changes |NGInlineFragmentTraversalTest| to ignore when NGFragmentItem
runtime feature enabled because NGFragmentItem doesn't use it.

Bug: 982194
Change-Id: I2fc93d85a41813d61ee0e7f6a2000dd968dc4e27
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2108459
Commit-Queue: Kent Tamura <tkent@chromium.org>
Auto-Submit: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#751637}

third_party/blink/renderer/core/layout/ng/inline/ng_inline_fragment_traversal_test.cc

@@ -50,6 +50,10 @@ class NGInlineFragmentTraversalTest : public NGLayoutTest {
   }
 
 TEST_F(NGInlineFragmentTraversalTest, DescendantsOf) {
+  if (RuntimeEnabledFeatures::LayoutNGFragmentItemEnabled()) {
+    // NGFragmentItem doesn't use |NGInlineFragmentTraversal|.
+    return;
+  }
   SetBodyInnerHTML(
       "<style>* { border: 1px solid}</style>"
       "<div id=t>foo<b id=b>bar</b><br>baz</div>");