[Oilpan] [Reland] Migrate classes under core/fetch to Oilpan heap

Source/core/loader/FrameFetchContext.h

Index: Source/core/loader/FrameFetchContext.h
diff --git a/Source/core/loader/FrameFetchContext.h b/Source/core/loader/FrameFetchContext.h
index f4b79eb40ec58b5b3fff0b0d987f2429d125402d..76e42705791eac1463841905257529192645f061 100644
--- a/Source/core/loader/FrameFetchContext.h
+++ b/Source/core/loader/FrameFetchContext.h
@@ -50,9 +50,9 @@ class ResourceRequest;
 
 class CORE_EXPORT FrameFetchContext final : public FetchContext {
 public:
-    static PassRefPtrWillBeRawPtr<ResourceFetcher> createContextAndFetcher(DocumentLoader* loader)
+    static ResourceFetcher* createContextAndFetcher(DocumentLoader* loader)
     {
-        return ResourceFetcher::create(adoptPtrWillBeNoop(new FrameFetchContext(loader)));
+        return ResourceFetcher::create(new FrameFetchContext(loader));
     }
 
     static void provideDocumentToContext(FetchContext& context, Document* document)