Make CSSParserContext be garbage collected.

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

Index: third_party/WebKit/Source/core/css/CSSGroupingRule.cpp
diff --git a/third_party/WebKit/Source/core/css/CSSGroupingRule.cpp b/third_party/WebKit/Source/core/css/CSSGroupingRule.cpp
index f9b8541c86f9b1667b7ca08ac9d35e365040d578..b206595084bc34743d08b179c46a3fc7342cd461 100644
--- a/third_party/WebKit/Source/core/css/CSSGroupingRule.cpp
+++ b/third_party/WebKit/Source/core/css/CSSGroupingRule.cpp
@@ -62,7 +62,8 @@ unsigned CSSGroupingRule::insertRule(const String& ruleString,
   }
 
   CSSStyleSheet* styleSheet = parentStyleSheet();
-  CSSParserContext context(parserContext(), UseCounter::getFrom(styleSheet));
+  CSSParserContext* context =
+      new CSSParserContext(parserContext(), UseCounter::getFrom(styleSheet));

[haraken, 2017/01/11 02:42:18]

Maybe we want to have a factory method. CSSParserContext::create(...).

[rune, 2017/01/11 12:59:26]

+1

[Bret, 2017/01/11 23:05:15]

Added for CSSStyleSheet and StyleSheetContents. Though I wonder if it should be
named CSSParserContext::copy instead?

   StyleRuleBase* newRule = CSSParser::parseRule(
       context, styleSheet ? styleSheet->contents() : nullptr, ruleString);
   if (!newRule) {