Use static cache for UFMatch lookups to improve performance

[colemanw]

Overview

Avoid excessive database hits by caching the UF/CID match records.

Before

More db lookups; slower

After

Fewer db lookups; faster

Notes

This is a supplement to #12576 which can potentially cause the CRM_Core_BAO_UFMatch::getUFId() to be called dozens of times per request. This caching ensures that we don't suffer a performance hit in doing so.

[civibot]

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[eileenmcnaughton]

@colemanw ... nope

[colemanw]

Whoops, php really don't like it when you try to check a key for a nonexistent array. Now fixed.

[colemanw]

@civicrm-builder retest this please

[colemanw]

@eileenmcnaughton ... yep

[eileenmcnaughton]

I read through this & stepped through this. The getUFId function is called 4 times from the contact summary page so this eliminated 3 DB queries.

The getContactID is called when editing a user but no obvious query reduction.

I only tried this on a single domain but I feel like it's pretty safe having stepped through it in a debugger & I guess it can sneak through without a test