Missing m_failedParsing=true for unresolved namespace.

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 be1b17a26a02cabb1a8b16428e29047761661e2a..3881cd2cde78aaf53bd94fa9f76c70d09babbae7 100644
--- a/third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp
+++ b/third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp
@@ -304,8 +304,10 @@ PassOwnPtr<CSSParserSelector> CSSSelectorParser::consumeCompoundSelector(CSSPars
 
     if (!compoundSelector) {
         AtomicString namespaceURI = determineNamespace(namespacePrefix);
-        if (namespaceURI.isNull())
+        if (namespaceURI.isNull()) {
+            m_failedParsing = true;
             return nullptr;
+        }
         return CSSParserSelector::create(QualifiedName(namespacePrefix, elementName, namespaceURI));
     }
     prependTypeSelectorIfNeeded(namespacePrefix, elementName, compoundSelector.get());