Allow simple selectors after ::content for compat.

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

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/css/parser/CSSSelectorParser.h"
 
 #include "core/css/CSSSelectorList.h"
 #include "core/css/StyleSheetContents.h"
 #include "core/frame/UseCounter.h"
 #include "platform/RuntimeEnabledFeatures.h"
@@ skipping 240 matching lines @@
         return isUserActionPseudoClass(pseudoClass);
     default:
         return false;
     }
 }
 
 bool isSimpleSelectorValidAfterPseudoElement(const CSSParserSelector& simpleSelector, CSSSelector::PseudoType compoundPseudoElement)
 {
     if (compoundPseudoElement == CSSSelector::PseudoUnknown)
         return true;
+    if (compoundPseudoElement == CSSSelector::PseudoContent)
+        return simpleSelector.match() != CSSSelector::PseudoElement;
     if (simpleSelector.match() != CSSSelector::PseudoClass)
         return false;
     CSSSelector::PseudoType pseudo = simpleSelector.pseudoType();
     if (pseudo == CSSSelector::PseudoNot) {
         ASSERT(simpleSelector.selectorList());
         ASSERT(simpleSelector.selectorList()->first());
         ASSERT(!simpleSelector.selectorList()->first()->tagHistory());
         pseudo = simpleSelector.selectorList()->first()->getPseudoType();
     }
     return isPseudoClassValidAfterPseudoElement(pseudo, compoundPseudoElement);
@@ skipping 510 matching lines @@
 
     if (!splitAfter || !splitAfter->tagHistory())
         return compoundSelector;
 
     OwnPtr<CSSParserSelector> secondCompound = splitAfter->releaseTagHistory();
     secondCompound->appendTagHistory(secondCompound->pseudoType() == CSSSelector::PseudoSlotted ? CSSSelector::ShadowSlot : CSSSelector::ShadowPseudo, compoundSelector);
     return secondCompound.release();
 }
 
 } // namespace blink