Fatal error when the Media module is not installed

Problem/Motivation

After trying to update to SVG Image Field 2.3.6 I get the following error:

PHP Fatal error: Uncaught Error: Class "Drupal\media\Plugin\media\Source\File" not found in /web/modules/contrib/svg_image_field/src/Plugin/media/Source/ScalableVectorGraphic.php:21

I do not have the Media module installed.

Details:

→ drush cr
PHP Fatal error:  Uncaught Error: Class "Drupal\media\Plugin\media\Source\File" not found in /web/modules/contrib/svg_image_field/src/Plugin/media/Source/ScalableVectorGraphic.php:21
Stack trace:
#0 /vendor/composer/ClassLoader.php(576): include()
#1 /vendor/composer/ClassLoader.php(427): Composer\Autoload\{closure}()
#2 [internal function]: Composer\Autoload\ClassLoader->loadClass('Drupal\\svg_imag...')
#3 /web/modules/contrib/svg_image_field/svg_image_field.module(14): class_alias('\\Drupal\\svg_ima...', '\\Drupal\\svg_ima...')
#4 /web/core/lib/Drupal/Core/Extension/Extension.php(153): include_once()
#5 /web/core/lib/Drupal/Core/Extension/ModuleHandler.php(128): Drupal\Core\Extension\Extension->load()
#6 /web/core/lib/Drupal/Core/Extension/ModuleHandler.php(141): Drupal\Core\Extension\ModuleHandler->load('svg_image_field')
#7 /web/core/lib/Drupal/Core/DrupalKernel.php(615): Drupal\Core\Extension\ModuleHandler->loadAll()
#8 /web/core/includes/utility.inc(35): Drupal\Core\DrupalKernel->preHandle(Object(Symfony\Component\HttpFoundation\Request))
#9 /vendor/drush/drush/src/Commands/core/CacheRebuildCommands.php(70): drupal_rebuild(Object(Composer\Autoload\ClassLoader), Object(Symfony\Component\HttpFoundation\Request))
#10 [internal function]: Drush\Commands\core\CacheRebuildCommands->rebuild(Array)
#11 /vendor/consolidation/annotated-command/src/CommandProcessor.php(276): call_user_func_array(Array, Array)
#12 /vendor/consolidation/annotated-command/src/CommandProcessor.php(212): Consolidation\AnnotatedCommand\CommandProcessor->runCommandCallback(Array, Object(Consolidation\AnnotatedCommand\CommandData))
#13 /vendor/consolidation/annotated-command/src/CommandProcessor.php(175): Consolidation\AnnotatedCommand\CommandProcessor->validateRunAndAlter(Array, Array, Object(Consolidation\AnnotatedCommand\CommandData))
#14 /vendor/consolidation/annotated-command/src/AnnotatedCommand.php(389): Consolidation\AnnotatedCommand\CommandProcessor->process(Object(Symfony\Component\Console\Output\ConsoleOutput), Array, Array, Object(Consolidation\AnnotatedCommand\CommandData))
#15 /vendor/symfony/console/Command/Command.php(326): Consolidation\AnnotatedCommand\AnnotatedCommand->execute(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#16 /vendor/symfony/console/Application.php(1088): Symfony\Component\Console\Command\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#17 /vendor/symfony/console/Application.php(324): Symfony\Component\Console\Application->doRunCommand(Object(Consolidation\AnnotatedCommand\AnnotatedCommand), Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#18 /vendor/symfony/console/Application.php(175): Symfony\Component\Console\Application->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#19 /vendor/drush/drush/src/Runtime/Runtime.php(110): Symfony\Component\Console\Application->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#20 /vendor/drush/drush/src/Runtime/Runtime.php(40): Drush\Runtime\Runtime->doRun(Array, Object(Symfony\Component\Console\Output\ConsoleOutput))
#21 /vendor/drush/drush/drush.php(139): Drush\Runtime\Runtime->run(Array)
#22 /vendor/drush/drush/drush(4): require()
#23 /vendor/bin/drush(119): include()
#24 {main}

thrown in /web/modules/contrib/svg_image_field/src/Plugin/media/Source/ScalableVectorGraphic.php on line 21

[warning] Drush command terminated abnormally.

It is caused by the class_alias() call in svg_image_field.module. That apparently caused the file ScalableVectorGraphic.php to be loaded and if the Media module is not installed it cannot find \Drupal\media\Plugin\media\Source\File.

Steps to reproduce

1. Have a Drupal site that does not have the Media module installed.
2. Install svg_image_field 2.3.6

Proposed resolution

Check if the class \Drupal\media\Plugin\media\Source\File exists before making the class_alias() call.

Remaining tasks

• Add an automated test that demonstrates the problem.
• Implement the proposed resolution.
• Review.
• Merge.

User interface changes

None.

API changes

None.

Data model changes

None.