BUG Safely handle empty injector factory responses

[tractorcow]

Fixes issue with ImageBackendFactory returning null and breaking injector

[Warning] Creating default object from empty value
GET /admin/settings/
Line 795 in C:\wamp64\www\timezoneone\vendor\silverstripe\framework\src\Core\Injector\Injector.php

Source
786 The name of the property to set
787 @param mixed $value
788 The value to set
789 /
790 protected function setObjectProperty($object, $name, $value)
791 {
792 if (ClassInfo::hasMethod($object, 'set' . $name)) {
793 $object->{'set' . $name}($value);
794 } else {
795 $object->$name = $value;
796 }
797 }
798
799 /*
800 @deprecated 4.0.0:5.0.0 Use Injector::has() instead
801 * @param $name
Trace
Monolog\ErrorHandler->handleError(2, Creating default object from empty value, C:\wamp64\www\timezoneone\vendor\silverstripe\framework\src\Core\Injector\Injector.php, 795, Array)
Injector.php:795
SilverStripe\Core\Injector\Injector->setObjectProperty(, Quality, 50)
Injector.php:637
SilverStripe\Core\Injector\Injector->inject(, SilverStripe\Assets\Image_Backend)
Injector.php:606
SilverStripe\Core\Injector\Injector->instantiate(Array, SilverStripe\Assets\Image_Backend, prototype)
Injector.php:988
SilverStripe\Core\Injector\Injector->getNamedService(SilverStripe\Assets\Image_Backend, , Array)
Injector.php:941
SilverStripe\Core\Injector\Injector->get(SilverStripe\Assets\Image_Backend, , Array)
Injector.php:1111
SilverStripe\Core\Injector\Injector->createWithArgs(SilverStripe\Assets\Image_Backend, Array)
ImageManipulation.php:713
SilverStripe\Assets\File->getImageBackend()
ImageManipulation.php:727
SilverStripe\Assets\File->getWidth()
AssetAdmin.php:1166
SilverStripe\AssetAdmin\Controller\AssetAdmin->getObjectFromData(SilverStripe\Assets\Image)
UploadField.php:208
SilverStripe\AssetAdmin\Forms\UploadField->getEncodedItems()
UploadField.php:193
SilverStripe\AssetAdmin\Forms\UploadField->getSchemaStateDefaults()
FormField.php:1562
SilverStripe\Forms\FormField->getSchemaState()
UploadField.php:276
SilverStripe\AssetAdmin\Forms\UploadField->getAttributes()
FormField.php:701
....