Speed up register_core_block_style_handles() $register_style check

[josephscott]

https://core.trac.wordpress.org/ticket/65779

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Props josephscott, mukesh27.

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[mukeshpanchal27]

If possible can you share the performance number?

[josephscott]

See the original ticket: https://core.trac.wordpress.org/ticket/65779#comment:1

I confirmed that this speeds up register_core_block_style_handles() on my local WordPress 7.0.2 release. I tested by adding hrtime() to the stop and bottom of that function and writing the result with error_log(). Then I requested the Hello World post. This was M5 Macbook Pro.

Median for 10 runs with current is_array() code: 2.434125 ms
Median for 10 runs with isset() code: 1.352646 ms

That is a 44% reduction in how long register_core_block_style_handles() takes to finish. It hooks into init so it runs early and often.

[mukeshpanchal27]

Nice! Thanks for sharing 🙌

[mukeshpanchal27]

Additional props for folks who works on 12798

Props khokansardar, irozum.