Problem description

segmentation fault, if close client before finely client.waitForReady.

Reproduction steps

1. Create and run client, server(or only client).
2. Call client.waitForReady
3. Wait(1ms-10ms)
4. Call client.close
5. Catch segfault

Repository with example: https://github.com/theltybc/example_for_issue_grpc.git

Environment

• OS name, version and architecture: Ubuntu mate 16.04.4 LTS (Xenial Xerus) amd64
• Node version - 9.2.0
• Node installation method - from site
• Package version [1.13.0, 1.14.0]

Additional context

waitForReady call methods of client.$channel. Any method of channel cause an segfault