Literal AtomicString construction can rely on strlen optimization.

third_party/WebKit/Source/core/html/shadow/DateTimeFieldElement.cpp

 /*
  * Copyright (C) 2012 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:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 141 matching lines @@
 void DateTimeFieldElement::focusOnNextField()
 {
     if (!m_fieldOwner)
         return;
     m_fieldOwner->focusOnNextField(*this);
 }
 
 void DateTimeFieldElement::initialize(const AtomicString& pseudo, const String& axHelpText, int axMinimum, int axMaximum)
 {
     // On accessibility, DateTimeFieldElement acts like spin button.
-    setAttribute(roleAttr, AtomicString("spinbutton", AtomicString::ConstructFromLiteral));
+    setAttribute(roleAttr, AtomicString("spinbutton"));
     setAttribute(aria_valuetextAttr, AtomicString(emptyValueAXText()));
     setAttribute(aria_valueminAttr, AtomicString::number(axMinimum));
     setAttribute(aria_valuemaxAttr, AtomicString::number(axMaximum));
 
     setAttribute(aria_helpAttr, AtomicString(axHelpText));
     setShadowPseudoId(pseudo);
     appendChild(Text::create(document(), visibleValue()));
 }
 
 bool DateTimeFieldElement::isDateTimeFieldElement() const
@@ skipping 67 matching lines @@
 }
 
 int DateTimeFieldElement::valueForARIAValueNow() const
 {
     return valueAsInteger();
 }
 
 } // namespace blink
 
 #endif