Avoid string allocation when parsing CSSPrimitiveValue::UnitType

third_party/WebKit/Source/core/css/parser/CSSParserToken.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/CSSParserToken.h"
 
 #include "core/css/CSSMarkup.h"
+#include "core/css/CSSPrimitiveValueUnitTrie.h"
 #include "core/css/parser/CSSPropertyParser.h"
 #include "wtf/HashMap.h"
 #include "wtf/text/StringBuilder.h"
 #include <limits.h>
 
 namespace blink {
 
 CSSParserToken::CSSParserToken(CSSParserTokenType type, BlockType blockType)
     : m_type(type)
     , m_blockType(blockType)
@@ skipping 43 matching lines @@
     , m_hashTokenType(type)
 {
     initValueFromCSSParserString(value);
 }
 
 void CSSParserToken::convertToDimensionWithUnit(CSSParserString unit)
 {
     ASSERT(m_type == NumberToken);
     m_type = DimensionToken;
     initValueFromCSSParserString(unit);
-    m_unit = static_cast<unsigned>(CSSPrimitiveValue::fromName(unit));
+
+    if (unit.is8Bit())
+        m_unit = static_cast<unsigned>(lookupCSSPrimitiveValueUnit(unit.characters8(), unit.length()));
+    else
+        m_unit = static_cast<unsigned>(lookupCSSPrimitiveValueUnit(unit.characters16(), unit.length()));
 }
 
 void CSSParserToken::convertToPercentage()
 {
     ASSERT(m_type == NumberToken);
     m_type = PercentageToken;
     m_unit = static_cast<unsigned>(CSSPrimitiveValue::UnitType::Percentage);
 }
 
 UChar CSSParserToken::delimiter() const
@@ skipping 201 matching lines @@
         return builder.append('}');
 
     case EOFToken:
     case CommentToken:
         ASSERT_NOT_REACHED();
         return;
     }
 }
 
 } // namespace blink