Don't add rule features across ::content.

third_party/WebKit/Source/core/css/RuleFeatureSetTest.cpp

 // Copyright 2015 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/RuleFeature.h"
 
 #include "core/css/CSSSelectorList.h"
 #include "core/css/RuleSet.h"
 #include "core/css/StylePropertySet.h"
 #include "core/css/StyleRule.h"
@@ skipping 95 matching lines @@
     }
 
     void expectClassInvalidation(const AtomicString& className, InvalidationSetVector& invalidationSets)
     {
         EXPECT_EQ(1u, invalidationSets.size());
         HashSet<AtomicString> classes = classSet(*invalidationSets[0]);
         EXPECT_EQ(1u, classes.size());
         EXPECT_TRUE(classes.contains(className));
     }
 
+    void expectNoClassInvalidation(const AtomicString& className, InvalidationSetVector& invalidationSets)

[Eric Willigers, 2016/01/07 03:50:00]

This isn't being used.

Perhaps call it from a test that has ".a ::content .b" only?

[rune, 2016/01/07 09:55:18]

The reason I didn't use it was because it will crash when there is no class set.
I would need another access method in InvalidationSet to test this.

Removing this.

+    {
+        EXPECT_EQ(1u, invalidationSets.size());
+        HashSet<AtomicString> classes = classSet(*invalidationSets[0]);
+        EXPECT_EQ(0u, classes.size());
+    }
+
     void expectSiblingInvalidation(unsigned maxDirectAdjacentSelectors, const AtomicString& siblingName, InvalidationSetVector& invalidationSets)
     {
         EXPECT_EQ(1u, invalidationSets.size());
         const SiblingInvalidationSet& siblingInvalidationSet = toSiblingInvalidationSet(*invalidationSets[0]);
         HashSet<AtomicString> classes = classSet(siblingInvalidationSet);
         EXPECT_EQ(1u, classes.size());
         EXPECT_TRUE(classes.contains(siblingName));
         EXPECT_EQ(maxDirectAdjacentSelectors, siblingInvalidationSet.maxDirectAdjacentSelectors());
     }
 
@@ skipping 188 matching lines @@
 
 TEST_F(RuleFeatureSetTest, tagName)
 {
     updateInvalidationSets(":valid e");
 
     InvalidationLists invalidationLists;
     collectInvalidationSetsForPseudoClass(invalidationLists, CSSSelector::PseudoValid);
     expectTagNameInvalidation("e", invalidationLists.descendants);
 }
 
+TEST_F(RuleFeatureSetTest, contentPseudo)
+{
+    updateInvalidationSets(".a ::content .b");
+    updateInvalidationSets(".a .c");
+
+    InvalidationLists invalidationLists;
+    collectInvalidationSetsForClass(invalidationLists, "a");
+    expectClassInvalidation("c", invalidationLists.descendants);
+
+    updateInvalidationSets(".a .b");
+
+    invalidationLists.descendants.clear();
+    collectInvalidationSetsForClass(invalidationLists, "a");
+    expectClassesInvalidation("b", "c", invalidationLists.descendants);
+}
+
 } // namespace blink