CSS: Avoid invalidating style when only descendants need updating

LayoutTests/fast/css/invalidation/targeted-class-any-pseudo.html

Index: LayoutTests/fast/css/invalidation/targeted-class-any-pseudo.html
diff --git a/LayoutTests/fast/css/invalidation/targeted-class-any-pseudo.html b/LayoutTests/fast/css/invalidation/targeted-class-any-pseudo.html
index 35c23fbf6775023f9908d1cea823671198e6e839..ad4ba2989323326cd1b165bafcc28feba410c41c 100644
--- a/LayoutTests/fast/css/invalidation/targeted-class-any-pseudo.html
+++ b/LayoutTests/fast/css/invalidation/targeted-class-any-pseudo.html
@@ -72,14 +72,14 @@ document.body.offsetLeft; // force style recalc.
 
 document.getElementById("t2").className = "a2";
 if (window.internals)
-    shouldBe("internals.updateStyleAndReturnAffectedElementCount()", "2");
+    shouldBe("internals.updateStyleAndReturnAffectedElementCount()", "1");
 shouldBe("getComputedStyle(b2, null).backgroundColor", "green");
 
 document.body.offsetLeft; // force style recalc.
 
 document.getElementById("t3").className = "a3";
 if (window.internals)
-    shouldBe("internals.updateStyleAndReturnAffectedElementCount()", "3");
+    shouldBe("internals.updateStyleAndReturnAffectedElementCount()", "2");
 shouldBe("getComputedStyle(b3, null).backgroundColor", "green");
 shouldBe("getComputedStyle(c3, null).backgroundColor", "green");