[FLINK-13280] Revert blink changes in DateTimeUtils, and keep it same as flink version.

• Type: Sub-task
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 1.9.0, 1.10.0
• Fix Version/s: 1.9.0
• Component/s: Table SQL / Planner
• Labels: pull-request-available
• Assignee: Zhenghua Gao
• Reporter: Zhenghua Gao
• Created: 16/Jul/19 01:45
• Updated: 01/Aug/19 10:57
• Resolved: 18/Jul/19 01:51

Description

            This class have some diff between flink/blink planner:

• Blink intros some constants (e.g., MICROS_PER_DAY, SECONDS_PER_DAY), inner use, it does not matter.
• Blink intros a function unixDateTimeToString (new)
• Blink changes the behavior of some function
• dateStringToUnixDate: only used in test & codegen now, can be moved into another util class
• timeStringToUnixDate: only used in test & codegen now, can be moved into another util class

• Blink intros USER TimeZone, but now it’s always UTC TimeZone, so it does not matter

Issue Links

• links to: GitHub Pull Request #9124