Don't use Vector<UChar> to build strings

Source/core/css/CSSPrimitiveValue.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2012 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 1007 matching lines @@
         case CSS_QUAD:
             text = getQuadValue()->cssText();
             break;
         case CSS_RGBCOLOR:
         case CSS_PARSER_HEXCOLOR: {
             RGBA32 rgbColor = m_value.rgbcolor;
             if (m_primitiveUnitType == CSS_PARSER_HEXCOLOR)
                 Color::parseHexColor(m_value.string, rgbColor);
             Color color(rgbColor);
 
-            Vector<LChar> result;
-            result.reserveInitialCapacity(32);
+            StringBuilder result;
+            result.reserveCapacity(32);
             bool colorHasAlpha = color.hasAlpha();
             if (colorHasAlpha)
                 result.append("rgba(", 5);
             else
                 result.append("rgb(", 4);
 
-            appendNumber(result, static_cast<unsigned char>(color.red()));
+            result.appendNumber(static_cast<unsigned char>(color.red()));
             result.append(", ", 2);
 
-            appendNumber(result, static_cast<unsigned char>(color.green()));
+            result.appendNumber(static_cast<unsigned char>(color.green()));
             result.append(", ", 2);
 
-            appendNumber(result, static_cast<unsigned char>(color.blue()));
+            result.appendNumber(static_cast<unsigned char>(color.blue()));
             if (colorHasAlpha) {
                 result.append(", ", 2);
 
                 NumberToStringBuffer buffer;
                 const char* alphaString = numberToFixedPrecisionString(color.alpha() / 255.0f, 6, buffer, true);
                 result.append(alphaString, strlen(alphaString));
             }
 
             result.append(')');
-            text = String::adopt(result);
+            text = result.toString();
             break;
         }
         case CSS_PAIR:
             text = getPairValue()->cssText();
             break;
         case CSS_PARSER_OPERATOR: {
             char c = static_cast<char>(m_value.parserOperator);
             text = String(&c, 1U);
             break;
         }
@@ skipping 238 matching lines @@
         return m_value.valueID == other.m_value.valueID;
     case CSS_CALC:
         return m_value.calc && other.m_value.calc && m_value.calc->equals(*other.m_value.calc);
     case CSS_SHAPE:
         return m_value.shape && other.m_value.shape && m_value.shape->equals(*other.m_value.shape);
     }
     return false;
 }
 
 } // namespace WebCore