Remove containsAttributeSelector() checks.

sky/engine/core/css/SelectorChecker.cpp

Index: sky/engine/core/css/SelectorChecker.cpp
diff --git a/sky/engine/core/css/SelectorChecker.cpp b/sky/engine/core/css/SelectorChecker.cpp
index 0839e84cf08eb55753a2dc6614cc644c5c451530..8050254cd6f45b01d4e61acf80b5a4fb96c18aea 100644
--- a/sky/engine/core/css/SelectorChecker.cpp
+++ b/sky/engine/core/css/SelectorChecker.cpp
@@ -208,7 +208,11 @@ bool SelectorChecker::checkOne(const SelectorCheckingContext& context) const
     case CSSSelector::Contain:
     case CSSSelector::Begin:
     case CSSSelector::End:
-        return anyAttributeMatches(element, selector.match(), selector);
+        if (anyAttributeMatches(element, selector.match(), selector)) {
+            if (m_mode == ResolvingStyle && context.elementStyle)
+                context.elementStyle->setUnique();
+        }
+        return false;
     case CSSSelector::PseudoClass:
         return checkPseudoClass(context);
     // FIXME(sky): Remove pseudo elements completely.