Bug 239967 prototype for nsScriptSecurityManager::GetPrincipalFromContext is wrong

r=dveditz sr=dveditz

caps/src/nsScriptSecurityManager.cpp

@@ -1775,7 +1775,7 @@ nsScriptSecurityManager::GetCodebasePrincipal(nsIURI *aURI,
     return NS_OK;
 }
 
-nsresult
+NS_IMETHODIMP
 nsScriptSecurityManager::GetPrincipalFromContext(JSContext *cx,
                                                  nsIPrincipal **result)
 {