Free HashSets on setWholeSubtreeInvalid.

Source/core/css/analyzer/DescendantInvalidationSet.h

Index: Source/core/css/analyzer/DescendantInvalidationSet.h
diff --git a/Source/core/css/analyzer/DescendantInvalidationSet.h b/Source/core/css/analyzer/DescendantInvalidationSet.h
index d2ba761d601cf0808863f8e2748750eabd86318a..40751446deed846ec1b4f2b0e2e89d4d6638da27 100644
--- a/Source/core/css/analyzer/DescendantInvalidationSet.h
+++ b/Source/core/css/analyzer/DescendantInvalidationSet.h
@@ -58,10 +58,10 @@ public:
     void addTagName(const AtomicString& tagName);
 
     // Appends the classes in this DescendantInvalidationSet to the vector.
-    void getClasses(Vector<AtomicString>& classes);
+    void getClasses(Vector<AtomicString>& classes) const;
 
-    void setWholeSubtreeInvalid() { m_allDescendantsMightBeInvalid = true; };
-    bool wholeSubtreeInvalid() { return m_allDescendantsMightBeInvalid; }
+    void setWholeSubtreeInvalid();
+    bool wholeSubtreeInvalid() const { return m_allDescendantsMightBeInvalid; }
 private:
     DescendantInvalidationSet();
 
@@ -69,7 +69,6 @@ private:
     HashSet<AtomicString>& ensureIdSet();
     HashSet<AtomicString>& ensureTagNameSet();
 
-    bool invalidateElementSubtreeInternal(Element*);
     // If true, all descendants might be invalidated, so a full subtree recalc is required.
     bool m_allDescendantsMightBeInvalid;
 
@@ -79,6 +78,17 @@ private:
     OwnPtr<HashSet<AtomicString> > m_tagNames;
 };
 
+inline void DescendantInvalidationSet::setWholeSubtreeInvalid()

[ojan, 2014/02/25 00:30:53]

Did you actually see performance difference in making this inline or just
keeping it inline because it used to be so before? If the former, LGTM. If the
latter, I'd prefer that this be moved to the cpp file and not inlined. 

[rune, 2014/02/25 08:36:17]

https://codereview.chromium.org/179483002/

+{
+    if (m_allDescendantsMightBeInvalid)
+        return;
+
+    m_allDescendantsMightBeInvalid = true;
+    m_classes = nullptr;
+    m_ids = nullptr;
+    m_tagNames = nullptr;
+}
+
 } // namespace WebCore
 
 #endif // DescendantInvalidationSet_h