CSS Tokenizer: Add an on-stack tokenizer scope

Source/core/css/parser/SizesCalcParserTest.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 "config.h"
 #include "core/css/parser/SizesCalcParser.h"
 
 #include "core/MediaTypeNames.h"
 #include "core/css/CSSPrimitiveValue.h"
 #include "core/css/MediaValuesCached.h"
@@ skipping 99 matching lines @@
     data.monochromeBitsPerComponent = 0;
     data.primaryPointerType = PointerTypeFine;
     data.defaultFontSize = 16;
     data.threeDEnabled = true;
     data.mediaType = MediaTypeNames::screen;
     data.strictMode = true;
     data.displayMode = WebDisplayModeBrowser;
     RefPtr<MediaValues> mediaValues = MediaValuesCached::create(data);
 
     for (unsigned i = 0; testCases[i].input; ++i) {
-        Vector<CSSParserToken> tokens;
-        CSSTokenizer::tokenize(testCases[i].input, tokens);
-        SizesCalcParser calcParser(CSSParserTokenRange(tokens), mediaValues);
+        SizesCalcParser calcParser(CSSTokenizer::Scope(testCases[i].input).tokenRange(), mediaValues);
         ASSERT_EQ(testCases[i].valid, calcParser.isValid());
         if (calcParser.isValid())
             ASSERT_EQ(testCases[i].output, calcParser.result());
     }
 
     for (unsigned i = 0; testCases[i].input; ++i) {
         if (testCases[i].dontRunInCSSCalc)
             continue;
         verifyCSSCalc(testCases[i].input, testCases[i].output, testCases[i].valid, data.defaultFontSize, data.viewportWidth, data.viewportHeight);
     }
 }
 
 } // namespace