Fix ConstantArrayType creation for preg_split with PREG_SPLIT_OFFSET_CAPTURE

[herndlm]

Refs: #1484

Looks like it was forgotten to explicitly specifiy $nextAutoIndexes correctly in that edge case. And then it falls back to [0] which can break the ConstantArrayTypeBuilder (since the array keys 0 and 1 are explicitly specified already).

I quickly looked through most of the other ConstantArrayType creations but did not find any more problems.

Fyi the 3 errors, that looked fine to me, are

Emitted errors:
- Method Bug7554\Readline::_bindControlB() has parameter $line with no type specified
  in /home/martin/PhpstormProjects/phpstan-src/tests/PHPStan/Analyser/data/bug-7554.php on line 11

- Parameter #1 $value of function count expects array|Countable, array<int, array<int, int<0, max>|string>>|false given
  in /home/martin/PhpstormProjects/phpstan-src/tests/PHPStan/Analyser/data/bug-7554.php on line 25

- Cannot access offset int<1, max> on array<int, array{string, int<0, max>}>|false
  in /home/martin/PhpstormProjects/phpstan-src/tests/PHPStan/Analyser/data/bug-7554.php on line 26

[ondrejmirtes]

Awesome, great! What I'd love additionally is a test for https://github.com/phpstan/phpstan-src/blob/1.8.x/tests/PHPStan/Type/Constant/ConstantArrayTypeBuilderTest.php that shows the scenario that failed with the internal error 😊

[herndlm]

Added something, but I'm pretty sure you meant it differently :) let me know please what to adapt

[ondrejmirtes]

Oh, I didn't check the patch, I thought the bug was in ConstantArrayTypeBuilder, not the preg_split extension...

[ondrejmirtes]

I merged it without the last commit, thanks :)