Deprecate format_size() and use Drupal\Core\StringTranslation\ByteSizeMarkup instead

Problem/Motivation

format_size() is still a procedural function. Convert it to a object oriented code.

Proposed resolution

• Add a \Drupal\Core\StringTranslation\ByteSizeMarkup::create() method that returns TranslatableMarkup
• Deprecate and remove usages of format_size().
• Add related PHP unit tests.

Remaining tasks

review/commit

User interface changes

none

API changes

• format_size() is deprecated
• A new Drupal\Core\StringTranslation\ByteSizeMarkup class is added