Prevent ThreadableLoaderClient methods from being called after failure notification

Source/core/loader/DocumentThreadableLoader.h

Index: Source/core/loader/DocumentThreadableLoader.h
diff --git a/Source/core/loader/DocumentThreadableLoader.h b/Source/core/loader/DocumentThreadableLoader.h
index b5b9d9d9d53c546e69326c67511603dbf2777e1c..5a403e3504c55186d284601fb33cccea39353b1c 100644
--- a/Source/core/loader/DocumentThreadableLoader.h
+++ b/Source/core/loader/DocumentThreadableLoader.h
@@ -73,6 +73,8 @@ class CORE_EXPORT DocumentThreadableLoader final : public ThreadableLoader, priv
 
         DocumentThreadableLoader(Document&, ThreadableLoaderClient*, BlockingBehavior, const ResourceRequest&, const ThreadableLoaderOptions&, const ResourceLoaderOptions&);
 
+        void clear();
+
         // ResourceClient

[hiroshige, 2015/08/04 10:30:59]

The methods I listed in #8 corresponds
- ctor
- cancel()
- all methods between here and loadRequest() (L78-L118, inclusive) except for
reportResponseReceived().

(dataReceived() should be also included but I missed in #8)

[tyoshino (SeeGerritForStatus), 2015/08/26 12:57:33]

Thanks. This is done except for loadActualRequest() and loadRequest(). See my
last post for the reason why these are excluded.

         void notifyFinished(Resource*) override;
         // RawResourceClient