Issue #2321969 by rpayanm, subhojit777, prics, LinL, JeroenT, Temoor, prashantgoel, Mile23, pcambra, Sumi: Replace all instances of file_load(), file_load_multiple(), entity_load('file') and entity_load_multiple('file') with static method calls

Issue #1392754 by tss, justAChris, jhodgdon: Comply with new documentation standards for @file for namespaced class files

Issue #2394419 by hussainweb, cilefen, sachinwable: Clean-up file module test members - ensure property definition and use of camelCase naming convention

Issue #2155245 by ChristianAdamski, scor, areke: Use proper methods instead of directly calling $file->filename and $file->uri

Issue #2395395 by alexpott, effulgentsia, Gábor Hojtsy: TestBase lacks a config method to be used consistently in tests

Issue #697760 by sun: Replace getInfo() in tests with native phpDoc + annotations (following PHPUnit).

Issue #2074037 by Wim Leers, effulgentsia: Add drupalPostUrl() — drupalPost()/drupalPostAjax() are for forms only, D8 JS performs non-form HTTP requests.

Issue #2072561 by legolasbo: Remove Unused local variable () from /core/modules/file/lib/Drupal/file/Tests/SaveUploadTest.php.

Issue #1797252 by pwieck, andypost, dcam, xjm, Lars Toomre: Remove t() from assertion messages in file module tests.

Issue #1496480 by mrf, disasm, kbasarab, pfrenssen, cam8001, typhonius, Letharion, ACF, vijaycs85, heyrocker, Berdir, alexpott: Convert file system settings to the new configuration system.

Issue #1468328 by Berdir: Move file entity info, managed file, and file usage functionality into File module.

Issue #1184272 by Berdir, corvus_ch, sun: Remove deprecated $conditions support from entity controller.