dev/core#3502 - CiviEventDispatcher - Softer errors for not-ready. More comments.

[totten]

Overview

v5.50 is more likely to raise complaints about hooks that fire during bootstrap (as in the case of https://lab.civicrm.org/dev/core/-/issues/3502). This patch tries to turn-down the volume on such errors.

(This is the 5.51-rc variant of the patch. Stable patch is #23739.)

Before

• Throws exception.

After

• Shows a message to the web-user (trigger_error(...E_USER_WARNING))
• Logs a message for sysadmin (error_log()) with backtrace.

Comments

Two use-cases:

1. The easiest way to trigger an error is to hack boot() function, eg

    \CRM_Utils_Hook::singleton()->commonBuildModuleList('civicrm_boot');
   +\CRM_Utils_Hook::entityTypes($x);
    $bootServices['dispatcher.boot']->setDispatchPolicy($mainDispatchPolicy);

2. I also managed to [reproduce the same error as @francescbassas](https://lab.civicrm.org/dev/core/-/issues/3502#note_75272. Activating rules wasn't enough -- I needed also needed a rule to specifically react to logs.

[civibot]

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[totten]

Merge based on testing for the 5.50 variant.