Remove the compile time flag for DATALIST Element.

Source/core/rendering/RenderThemeChromiumSkia.cpp

Index: Source/core/rendering/RenderThemeChromiumSkia.cpp
diff --git a/Source/core/rendering/RenderThemeChromiumSkia.cpp b/Source/core/rendering/RenderThemeChromiumSkia.cpp
index 52baa05dea00ceab7fea82a2da4660ccac19f1c7..5022f97bdaea3f58f10054c99e5b33b6278ac91a 100644
--- a/Source/core/rendering/RenderThemeChromiumSkia.cpp
+++ b/Source/core/rendering/RenderThemeChromiumSkia.cpp
@@ -80,9 +80,10 @@ RenderThemeChromiumSkia::~RenderThemeChromiumSkia()
 // Use the Windows style sheets to match their metrics.
 String RenderThemeChromiumSkia::extraDefaultStyleSheet()
 {
-    return String(themeWinUserAgentStyleSheet, sizeof(themeWinUserAgentStyleSheet)) +
-           String(themeChromiumSkiaUserAgentStyleSheet, sizeof(themeChromiumSkiaUserAgentStyleSheet)) +
-           String(themeChromiumUserAgentStyleSheet, sizeof(themeChromiumUserAgentStyleSheet));
+    return RenderTheme::extraDefaultStyleSheet() +
+        String(themeWinUserAgentStyleSheet, sizeof(themeWinUserAgentStyleSheet)) +
+        String(themeChromiumSkiaUserAgentStyleSheet, sizeof(themeChromiumSkiaUserAgentStyleSheet)) +
+        String(themeChromiumUserAgentStyleSheet, sizeof(themeChromiumUserAgentStyleSheet));
 }
 
 String RenderThemeChromiumSkia::extraQuirksStyleSheet()