Remove ShadowDOMV1 runtime flag (status=stable)

third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp

Index: third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp
diff --git a/third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp b/third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp
index 25127417b716e9bda5c0a7e0b083ef24ffb096b4..e06c2906354825f128a8caeaaefc1804dfce32b8 100644
--- a/third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp
+++ b/third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp
@@ -557,8 +557,7 @@ std::unique_ptr<CSSParserSelector> CSSSelectorParser::consumePseudo(
       std::unique_ptr<CSSParserSelector> innerSelector =
           consumeCompoundSelector(block);
       block.consumeWhitespace();
-      if (!innerSelector || !block.atEnd() ||
-          !RuntimeEnabledFeatures::shadowDOMV1Enabled())
+      if (!innerSelector || !block.atEnd())
         return nullptr;
       Vector<std::unique_ptr<CSSParserSelector>> selectorVector;
       selectorVector.append(std::move(innerSelector));