Package leakcheck contains functions to check leaked goroutines.
Call "defer leakcheck.Check(t)" at the beginning of tests.
Check looks at the currently-running goroutines and checks if there are any interesting (created by gRPC) goroutines leaked. It waits up to 10 seconds in the error cases.
RegisterIgnoreGoroutine appends s into the ignore goroutine list. The goroutines whose stack trace contains s will not be identified as leaked goroutines. Not thread-safe, only call this function in init().
Errorfer is the interface that wraps the Errorf method. It's a subset of testing.TB to make it easy to use Check.