Split the CSSParserContext class out of CSSParserMode into its own file.

third_party/WebKit/Source/core/css/CSSSyntaxDescriptor.cpp

 // Copyright 2016 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/CSSSyntaxDescriptor.h"
 
 #include "core/css/CSSCustomPropertyDeclaration.h"
 #include "core/css/CSSURIValue.h"
 #include "core/css/CSSValueList.h"
 #include "core/css/CSSVariableReferenceValue.h"
+#include "core/css/parser/CSSParserContext.h"
 #include "core/css/parser/CSSParserIdioms.h"
 #include "core/css/parser/CSSPropertyParserHelpers.h"
 #include "core/css/parser/CSSVariableParser.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 
 namespace blink {
 
 void consumeWhitespace(const String& string, size_t& offset) {
   while (isHTMLSpace(string[offset]))
     offset++;
@@ skipping 182 matching lines @@
   range.consumeWhitespace();
   for (const CSSSyntaxComponent& component : m_syntaxComponents) {
     if (const CSSValue* result = consumeSyntaxComponent(component, range))
       return result;
   }
   return CSSVariableParser::parseRegisteredPropertyValue(range, true,
                                                          isAnimationTainted);
 }
 
 }  // namespace blink