Convert first letter into a pseudo element.

LayoutTests/fast/css/dynamic-class-pseudo-elements.html

Index: LayoutTests/fast/css/dynamic-class-pseudo-elements.html
diff --git a/LayoutTests/fast/css/dynamic-class-pseudo-elements.html b/LayoutTests/fast/css/dynamic-class-pseudo-elements.html
index 19c6f160d1b17c2778e9c79f2379a768db84cf8c..39d8ba9f8ce43f7cabdaeb417735fe9087a4d83b 100644
--- a/LayoutTests/fast/css/dynamic-class-pseudo-elements.html
+++ b/LayoutTests/fast/css/dynamic-class-pseudo-elements.html
@@ -81,7 +81,7 @@ forceLayout();
 t4.className = "a4";
 
 if (window.internals)
-    shouldBe("internals.updateStyleAndReturnAffectedElementCount()", "8");
+    shouldBe("internals.updateStyleAndReturnAffectedElementCount()", "10");

[dsinclair, 2014/09/27 03:21:21]

What does this check do? I'm not sure why the number went up, but I also don't
understand where the number came from?

[esprehn, 2014/09/30 09:00:29]

It's the number of Element instances that went through ::recalcStyle(). So
you're causing 2 more elements to go through recalcStyle in this test. Given the
number of first letters, is that correct?

 
 document.body.offsetLeft; // workaround for issue 351308
 shouldBe("getComputedStyle(r4, '::first-letter').backgroundColor", "green");