Create errors (especially cancellation errors) internally to WebCore, rather

Source/core/loader/EmptyClients.h

Index: Source/core/loader/EmptyClients.h
===================================================================
--- Source/core/loader/EmptyClients.h	(revision 148582)
+++ Source/core/loader/EmptyClients.h	(working copy)
@@ -239,8 +239,6 @@
     virtual void dispatchDecidePolicyForNewWindowAction(FramePolicyFunction, const NavigationAction&, const ResourceRequest&, PassRefPtr<FormState>, const String&) OVERRIDE;
     virtual void dispatchDecidePolicyForNavigationAction(FramePolicyFunction, const NavigationAction&, const ResourceRequest&, PassRefPtr<FormState>) OVERRIDE;
 
-    virtual void dispatchUnableToImplementPolicy(const ResourceError&) { }
-
     virtual void dispatchWillSendSubmitEvent(PassRefPtr<FormState>) OVERRIDE;
     virtual void dispatchWillSubmitForm(PassRefPtr<FormState>) OVERRIDE;
 
@@ -254,18 +252,8 @@
 
     virtual void committedLoad(DocumentLoader*, const char*, int) { }
     virtual void finishedLoading(DocumentLoader*) { }
-
-    virtual ResourceError cancelledError(const ResourceRequest&) { ResourceError error("", 0, "", ""); error.setIsCancellation(true); return error; }
-    virtual ResourceError cannotShowURLError(const ResourceRequest&) { return ResourceError("", 0, "", ""); }
     virtual ResourceError interruptedForPolicyChangeError(const ResourceRequest&) { return ResourceError("", 0, "", ""); }
 
-    virtual ResourceError cannotShowMIMETypeError(const ResourceResponse&) { return ResourceError("", 0, "", ""); }
-    virtual ResourceError fileDoesNotExistError(const ResourceResponse&) { return ResourceError("", 0, "", ""); }
-    virtual ResourceError pluginWillHandleLoadError(const ResourceResponse&) { return ResourceError("", 0, "", ""); }
-
-    virtual bool shouldFallBack(const ResourceError&) { return false; }
-
-    virtual bool canHandleRequest(const ResourceRequest&) const { return false; }
     virtual bool canShowMIMEType(const String&) const { return false; }
     virtual String generatedMIMETypeForURLScheme(const String&) const { return ""; }