variables: return error when setting statement summary variables to invalid values

[djshow832]

What problem does this PR solve?

Problem Summary:
System variables are transformed to a valid value according to min/max values. But this valid value is stored into TiKV, while the current server still uses the invalid value.
For example,

set global tidb_stmt_summary_refresh_interval = -1;

-1 is invalid and the value is transformed to 1 when validating it, and 1 is stored to mysql.global_variables table. However, 1 is not returned in the current SET statement, and the SET statement passes -1 to statement summary.

What is changed and how it works?

What's Changed:
Throw an error when it's set to an invalid value. This is simple and reasonable.

Related changes

• Need to cherry-pick to the release branch

Check List

Tests

• Unit test
• Manual test (add detailed scripts or steps below)

mysql> set global tidb_stmt_summary_refresh_interval=1<<31;
ERROR 1231 (42000): Variable 'tidb_stmt_summary_refresh_interval' can't be set to the value of '2147483648'
mysql> set session tidb_stmt_summary_refresh_interval=0;
ERROR 1231 (42000): Variable 'tidb_stmt_summary_refresh_interval' can't be set to the value of '0'

Side effects

• Breaking backward compatibility

Release note

• return error when setting statement summary system variables to invalid values.

[djshow832]

/run-all-tests

[AilinKid]

Rest LGTM

[AilinKid]

LGTM

[Deardrops]

LGTM

[djshow832]

/merge

[sre-bot]

/run-all-tests

[codecov]

Codecov Report

Merging #17108 into master will not change coverage.
The diff coverage is n/a.

@@             Coverage Diff             @@
##             master     #17108   +/-   ##
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  Coverage   80.2252%   80.2252%           
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  Files           510        510           
  Lines        140563     140563           
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  Hits         112767     112767           
  Misses        18819      18819           
  Partials       8977       8977           

[sre-bot]

cherry pick to release-4.0 in PR #17129