return NS_ERROR_NOT_IMPLEMENTED for some of the channel interface implementations

mailnews/imap/src/nsImapService.cpp

@@ -2137,15 +2137,13 @@ NS_IMETHODIMP nsImapService::GetDefaultPort(PRInt32 *aDefaultPort)
 NS_IMETHODIMP nsImapService::MakeAbsolute(const char *aRelativeSpec, nsIURI *aBaseURI, char **_retval)
 {
 	// no such thing as relative urls for smtp.....
-	NS_ASSERTION(0, "unimplemented");
-	return NS_OK;
+	return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP nsImapService::NewURI(const char *aSpec, nsIURI *aBaseURI, nsIURI **_retval)
 {
 	// i just haven't implemented this yet...I will be though....
-	NS_ASSERTION(0, "unimplemented");
-	return NS_OK;
+	return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP nsImapService::NewChannel(const char *verb, nsIURI *aURI, nsIEventSinkGetter *eventSinkGetter, nsIChannel **_retval)
@@ -2153,6 +2151,5 @@ NS_IMETHODIMP nsImapService::NewChannel(const char *verb, nsIURI *aURI, nsIEvent
 	// mscott - right now, I don't like the idea of returning channels to the caller. They just want us
 	// to run the url, they don't want a channel back...I'm going to be addressing this issue with
 	// the necko team in more detail later on.
-	NS_ASSERTION(0, "unimplemented");
-	return NS_OK;
+	return NS_ERROR_NOT_IMPLEMENTED;
 }