Fix non-Oilpan build following r373473.

third_party/WebKit/Source/core/css/StyleSheetContentsTest.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/StyleSheetContents.h"
 
 #include "core/css/CSSTestHelper.h"
 #include "core/css/parser/CSSParser.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
 TEST(StyleSheetContentsTest, InsertMediaRule)
 {
     CSSParserContext context(HTMLStandardMode, nullptr);
 
     RefPtrWillBeRawPtr<StyleSheetContents> styleSheet = StyleSheetContents::create(context);
     styleSheet->parseString("@namespace ns url(test);");
     EXPECT_EQ(1U, styleSheet->ruleCount());
 
     styleSheet->setMutable();
-    styleSheet->wrapperInsertRule(CSSParser::parseRule(context, styleSheet, "@media all { div { color: pink } }"), 0);
+    styleSheet->wrapperInsertRule(CSSParser::parseRule(context, styleSheet.get(), "@media all { div { color: pink } }"), 0);
     EXPECT_EQ(1U, styleSheet->ruleCount());
     EXPECT_FALSE(styleSheet->hasMediaQueries());
 
-    styleSheet->wrapperInsertRule(CSSParser::parseRule(context, styleSheet, "@media all { div { color: green } }"), 1);
+    styleSheet->wrapperInsertRule(CSSParser::parseRule(context, styleSheet.get(), "@media all { div { color: green } }"), 1);
     EXPECT_EQ(2U, styleSheet->ruleCount());
     EXPECT_TRUE(styleSheet->hasMediaQueries());
 }
 
 } // namespace blink