List marker pseudo elements.

Source/core/css/CSSTestHelper.cpp

Index: Source/core/css/CSSTestHelper.cpp
diff --git a/Source/core/css/CSSTestHelper.cpp b/Source/core/css/CSSTestHelper.cpp
index 93f16ae3edac7bc342c1dc9841c679b720a241b4..7f7819d44b5068a407fc2588cd1874155799893b 100644
--- a/Source/core/css/CSSTestHelper.cpp
+++ b/Source/core/css/CSSTestHelper.cpp
@@ -61,10 +61,15 @@ RuleSet& CSSTestHelper::ruleSet()
 
 void CSSTestHelper::addCSSRules(const char* cssText)
 {
-    TextPosition position;
     unsigned sheetLength = m_styleSheet->length();
-    m_styleSheet->contents()->parseStringAtPosition(cssText, position, true);
+    tryAddCSSRules(cssText);
     ASSERT_TRUE(m_styleSheet->length() > sheetLength);
 }
 
+void CSSTestHelper::tryAddCSSRules(const char* cssText)
+{
+    TextPosition position;
+    m_styleSheet->contents()->parseStringAtPosition(cssText, position, true);
+}
+
 } // namespace blink