Literal AtomicString construction can rely on strlen optimization.

third_party/WebKit/Source/core/dom/MutationRecord.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 152 matching lines @@
     const AtomicString& attributeName() override { return m_record->attributeName(); }
     const AtomicString& attributeNamespace() override { return m_record->attributeNamespace(); }
 
     String oldValue() override { return String(); }
 
     RefPtrWillBeMember<MutationRecord> m_record;
 };
 
 const AtomicString& ChildListRecord::type()
 {
-    DEFINE_STATIC_LOCAL(AtomicString, childList, ("childList", AtomicString::ConstructFromLiteral));
+    DEFINE_STATIC_LOCAL(AtomicString, childList, ("childList"));
     return childList;
 }
 
 const AtomicString& AttributesRecord::type()
 {
-    DEFINE_STATIC_LOCAL(AtomicString, attributes, ("attributes", AtomicString::ConstructFromLiteral));
+    DEFINE_STATIC_LOCAL(AtomicString, attributes, ("attributes"));
     return attributes;
 }
 
 const AtomicString& CharacterDataRecord::type()
 {
-    DEFINE_STATIC_LOCAL(AtomicString, characterData, ("characterData", AtomicString::ConstructFromLiteral));
+    DEFINE_STATIC_LOCAL(AtomicString, characterData, ("characterData"));
     return characterData;
 }
 
 } // namespace
 
 PassRefPtrWillBeRawPtr<MutationRecord> MutationRecord::createChildList(PassRefPtrWillBeRawPtr<Node> target, PassRefPtrWillBeRawPtr<StaticNodeList> added, PassRefPtrWillBeRawPtr<StaticNodeList> removed, PassRefPtrWillBeRawPtr<Node> previousSibling, PassRefPtrWillBeRawPtr<Node> nextSibling)
 {
     return adoptRefWillBeNoop(new ChildListRecord(target, added, removed, previousSibling, nextSibling));
 }
 
@@ skipping 10 matching lines @@
 PassRefPtrWillBeRawPtr<MutationRecord> MutationRecord::createWithNullOldValue(PassRefPtrWillBeRawPtr<MutationRecord> record)
 {
     return adoptRefWillBeNoop(new MutationRecordWithNullOldValue(record));
 }
 
 MutationRecord::~MutationRecord()
 {
 }
 
 } // namespace blink