Currently, we only include context id when there is a valid context and when at least one tensor in the arg list requires grad. However, even if the request does not contain any requires_grad tensor, the response might contain some, whose grad should still belong to the same context.

cc @pietern @mrshenli @pritamdamania87 @zhaojuanmao @satgera @rohan-varma @gqchen @aazzolini @xush6528