Cannot start tiflash if TimeZone is not set

[yeya24]

Bug Report

What version of Kubernetes are you using?

v1.15.2

What version of TiDB Operator are you using?

The latest release

What storage classes exist in the Kubernetes cluster and what are used for PD/TiKV pods?

What's the status of the TiDB cluster pods?

What did you do?

Deploy a TiDB cluster with TiFlash. However, I didn't set the TimeZone field in TiDBClusterSpec, because I thought the default value is UTC. However, TiFlash cannot start if TimeZone is not set explicitly. The error is

➜  tipocket git:(add-tiflash-crd) ✗ klo yeya24-tiflash-0 -c tiflash
Logging information to /data0/logs/server.log
Logging errors to /data0/logs/error.log
Poco::Exception. Code: 1000, e.code() = 0, e.displayText() = Exception: Could not determine time zone from TZ variable value: '': boost::filesystem::file_size: Operation not permitted: "/usr/share/zoneinfo", e.what() = Exception

If I set the TimeZone in the spec manually, then TiFlash can start correctly.

What did you expect to see?

If I didn't set the TimeZone field, TiFlash can still start normally, since it will use the default time zone UTC.

What did you see instead?

The time zone env var in TiFlash is "".
The problem is in the code below, I think we should use tc.TimeZone() instead of using tc.Spec.Timezone

		{
			Name:  "TZ",
			Value: tc.Spec.Timezone,
		},

[DanielZhangQD]

@yeya24 Yes, you're right! Thanks!
Please feel free to try it and feedback any issues to us.
BTW, scaling, upgrading, and failover are working in progress.