Show an indicator of critical extensions in the openssl_x509_parse() …

[StephenWall]

…output in a backwards compatible way.

Fixes #20310

[bukka]

This looks slightly strange. How about a new field criticalExtension that would contain string array of critical extension names?

[StephenWall]

This looks slightly strange. How about a new field criticalExtension that would contain string array of critical extension names?

To clarify, $info['extensions'] is unchanged and a new $info['criticalExtensions'] has a list of the names of critical extensions?

$info['extensions'] => array (
  'basicConstraints' => 'CA:FALSE',
  ...
)

$info['criticalExtensions'] => array(
  'basicConstraints'
)

[bukka]

Yes, exactly.

[StephenWall]

OK, self test runs cleanly, I think this is set.