Summary: Fix 17 trivial "Variable might not be defined" issues found by PHPStan static code analysis to have a little bit less noise (there are many more which makes it harder to find real problems). Defensive programming yadda yadda. ``` Line src/applications/people/controller/PhabricatorPeopleInviteSendController.php 136 Variable $actions might not be defined. 146 Variable $any_valid might not be defined. Line src/applications/phid/query/PhabricatorObjectListQuery.php 203 Variable $suffix_map might not be defined. Line src/applications/search/engine/PhabricatorProfileMenuEngine.php 420 Variable $builtins might not be defined. Line support/startup/PhabricatorClientLimit.php 204 Variable $bucket might not be defined. 241 Variable $min might not be defined. Line src/view/phui/PHUIRemarkupPreviewPanel.php 114 Variable $content might not be defined. Line src/view/phui/PHUIInfoView.php 109 Variable $icon might not be defined. Line src/view/phui/PHUICurtainObjectRefView.php 237 Variable $icon_view might not be defined. Line src/applications/maniphest/conduit/ManiphestConduitAPIMethod.php 161 Variable $comments might not be defined. Line src/applications/people/typeahead/PhabricatorPeopleDatasource.php 75 Variable $handles might not be defined. Line src/applications/settings/controller/PhabricatorSettingsMainController.php 117 Variable $user might not be defined. Line src/applications/files/engine/PhabricatorFileStorageEngine.php 327 Variable $engine might not be defined. Line src/infrastructure/cache/PhutilAPCKeyValueCache.php 33 Variable $result might not be defined. Line src/applications/config/engine/PhabricatorSetupEngine.php 50 Variable $issue might not be defined. Line src/applications/diffusion/management/DiffusionRepositoryStorageManagementPanel.php 314 Variable $refs might not be defined. Line src/applications/diffusion/DiffusionLintSaveRunner.php 123 Variable $all_files might not be defined. ``` Test Plan: Read the code; run static code analysis before and after. Reviewers: O1 Blessed Committers, mainframe98 Reviewed By: O1 Blessed Committers, mainframe98 Subscribers: mainframe98, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno Differential Revision: https://we.phorge.it/D26198